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diff --git a/src/main/resources/static/plugins/popper/popper.js b/src/main/resources/static/plugins/popper/popper.js
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+/**!
+ * @fileOverview Kickass library to create and place poppers near their reference elements.
+ * @version 1.16.1
+ * @license
+ * Copyright (c) 2016 Federico Zivolo and contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+var isBrowser = typeof window !== 'undefined' && typeof document !== 'undefined' && typeof navigator !== 'undefined';
+
+const timeoutDuration = function () {
+  const longerTimeoutBrowsers = ['Edge', 'Trident', 'Firefox'];
+  for (let i = 0; i < longerTimeoutBrowsers.length; i += 1) {
+    if (isBrowser && navigator.userAgent.indexOf(longerTimeoutBrowsers[i]) >= 0) {
+      return 1;
+    }
+  }
+  return 0;
+}();
+
+function microtaskDebounce(fn) {
+  let called = false;
+  return () => {
+    if (called) {
+      return;
+    }
+    called = true;
+    window.Promise.resolve().then(() => {
+      called = false;
+      fn();
+    });
+  };
+}
+
+function taskDebounce(fn) {
+  let scheduled = false;
+  return () => {
+    if (!scheduled) {
+      scheduled = true;
+      setTimeout(() => {
+        scheduled = false;
+        fn();
+      }, timeoutDuration);
+    }
+  };
+}
+
+const supportsMicroTasks = isBrowser && window.Promise;
+
+/**
+* Create a debounced version of a method, that's asynchronously deferred
+* but called in the minimum time possible.
+*
+* @method
+* @memberof Popper.Utils
+* @argument {Function} fn
+* @returns {Function}
+*/
+var debounce = supportsMicroTasks ? microtaskDebounce : taskDebounce;
+
+/**
+ * Check if the given variable is a function
+ * @method
+ * @memberof Popper.Utils
+ * @argument {Any} functionToCheck - variable to check
+ * @returns {Boolean} answer to: is a function?
+ */
+function isFunction(functionToCheck) {
+  const getType = {};
+  return functionToCheck && getType.toString.call(functionToCheck) === '[object Function]';
+}
+
+/**
+ * Get CSS computed property of the given element
+ * @method
+ * @memberof Popper.Utils
+ * @argument {Eement} element
+ * @argument {String} property
+ */
+function getStyleComputedProperty(element, property) {
+  if (element.nodeType !== 1) {
+    return [];
+  }
+  // NOTE: 1 DOM access here
+  const window = element.ownerDocument.defaultView;
+  const css = window.getComputedStyle(element, null);
+  return property ? css[property] : css;
+}
+
+/**
+ * Returns the parentNode or the host of the element
+ * @method
+ * @memberof Popper.Utils
+ * @argument {Element} element
+ * @returns {Element} parent
+ */
+function getParentNode(element) {
+  if (element.nodeName === 'HTML') {
+    return element;
+  }
+  return element.parentNode || element.host;
+}
+
+/**
+ * Returns the scrolling parent of the given element
+ * @method
+ * @memberof Popper.Utils
+ * @argument {Element} element
+ * @returns {Element} scroll parent
+ */
+function getScrollParent(element) {
+  // Return body, `getScroll` will take care to get the correct `scrollTop` from it
+  if (!element) {
+    return document.body;
+  }
+
+  switch (element.nodeName) {
+    case 'HTML':
+    case 'BODY':
+      return element.ownerDocument.body;
+    case '#document':
+      return element.body;
+  }
+
+  // Firefox want us to check `-x` and `-y` variations as well
+  const { overflow, overflowX, overflowY } = getStyleComputedProperty(element);
+  if (/(auto|scroll|overlay)/.test(overflow + overflowY + overflowX)) {
+    return element;
+  }
+
+  return getScrollParent(getParentNode(element));
+}
+
+/**
+ * Returns the reference node of the reference object, or the reference object itself.
+ * @method
+ * @memberof Popper.Utils
+ * @param {Element|Object} reference - the reference element (the popper will be relative to this)
+ * @returns {Element} parent
+ */
+function getReferenceNode(reference) {
+  return reference && reference.referenceNode ? reference.referenceNode : reference;
+}
+
+const isIE11 = isBrowser && !!(window.MSInputMethodContext && document.documentMode);
+const isIE10 = isBrowser && /MSIE 10/.test(navigator.userAgent);
+
+/**
+ * Determines if the browser is Internet Explorer
+ * @method
+ * @memberof Popper.Utils
+ * @param {Number} version to check
+ * @returns {Boolean} isIE
+ */
+function isIE(version) {
+  if (version === 11) {
+    return isIE11;
+  }
+  if (version === 10) {
+    return isIE10;
+  }
+  return isIE11 || isIE10;
+}
+
+/**
+ * Returns the offset parent of the given element
+ * @method
+ * @memberof Popper.Utils
+ * @argument {Element} element
+ * @returns {Element} offset parent
+ */
+function getOffsetParent(element) {
+  if (!element) {
+    return document.documentElement;
+  }
+
+  const noOffsetParent = isIE(10) ? document.body : null;
+
+  // NOTE: 1 DOM access here
+  let offsetParent = element.offsetParent || null;
+  // Skip hidden elements which don't have an offsetParent
+  while (offsetParent === noOffsetParent && element.nextElementSibling) {
+    offsetParent = (element = element.nextElementSibling).offsetParent;
+  }
+
+  const nodeName = offsetParent && offsetParent.nodeName;
+
+  if (!nodeName || nodeName === 'BODY' || nodeName === 'HTML') {
+    return element ? element.ownerDocument.documentElement : document.documentElement;
+  }
+
+  // .offsetParent will return the closest TH, TD or TABLE in case
+  // no offsetParent is present, I hate this job...
+  if (['TH', 'TD', 'TABLE'].indexOf(offsetParent.nodeName) !== -1 && getStyleComputedProperty(offsetParent, 'position') === 'static') {
+    return getOffsetParent(offsetParent);
+  }
+
+  return offsetParent;
+}
+
+function isOffsetContainer(element) {
+  const { nodeName } = element;
+  if (nodeName === 'BODY') {
+    return false;
+  }
+  return nodeName === 'HTML' || getOffsetParent(element.firstElementChild) === element;
+}
+
+/**
+ * Finds the root node (document, shadowDOM root) of the given element
+ * @method
+ * @memberof Popper.Utils
+ * @argument {Element} node
+ * @returns {Element} root node
+ */
+function getRoot(node) {
+  if (node.parentNode !== null) {
+    return getRoot(node.parentNode);
+  }
+
+  return node;
+}
+
+/**
+ * Finds the offset parent common to the two provided nodes
+ * @method
+ * @memberof Popper.Utils
+ * @argument {Element} element1
+ * @argument {Element} element2
+ * @returns {Element} common offset parent
+ */
+function findCommonOffsetParent(element1, element2) {
+  // This check is needed to avoid errors in case one of the elements isn't defined for any reason
+  if (!element1 || !element1.nodeType || !element2 || !element2.nodeType) {
+    return document.documentElement;
+  }
+
+  // Here we make sure to give as "start" the element that comes first in the DOM
+  const order = element1.compareDocumentPosition(element2) & Node.DOCUMENT_POSITION_FOLLOWING;
+  const start = order ? element1 : element2;
+  const end = order ? element2 : element1;
+
+  // Get common ancestor container
+  const range = document.createRange();
+  range.setStart(start, 0);
+  range.setEnd(end, 0);
+  const { commonAncestorContainer } = range;
+
+  // Both nodes are inside #document
+  if (element1 !== commonAncestorContainer && element2 !== commonAncestorContainer || start.contains(end)) {
+    if (isOffsetContainer(commonAncestorContainer)) {
+      return commonAncestorContainer;
+    }
+
+    return getOffsetParent(commonAncestorContainer);
+  }
+
+  // one of the nodes is inside shadowDOM, find which one
+  const element1root = getRoot(element1);
+  if (element1root.host) {
+    return findCommonOffsetParent(element1root.host, element2);
+  } else {
+    return findCommonOffsetParent(element1, getRoot(element2).host);
+  }
+}
+
+/**
+ * Gets the scroll value of the given element in the given side (top and left)
+ * @method
+ * @memberof Popper.Utils
+ * @argument {Element} element
+ * @argument {String} side `top` or `left`
+ * @returns {number} amount of scrolled pixels
+ */
+function getScroll(element, side = 'top') {
+  const upperSide = side === 'top' ? 'scrollTop' : 'scrollLeft';
+  const nodeName = element.nodeName;
+
+  if (nodeName === 'BODY' || nodeName === 'HTML') {
+    const html = element.ownerDocument.documentElement;
+    const scrollingElement = element.ownerDocument.scrollingElement || html;
+    return scrollingElement[upperSide];
+  }
+
+  return element[upperSide];
+}
+
+/*
+ * Sum or subtract the element scroll values (left and top) from a given rect object
+ * @method
+ * @memberof Popper.Utils
+ * @param {Object} rect - Rect object you want to change
+ * @param {HTMLElement} element - The element from the function reads the scroll values
+ * @param {Boolean} subtract - set to true if you want to subtract the scroll values
+ * @return {Object} rect - The modifier rect object
+ */
+function includeScroll(rect, element, subtract = false) {
+  const scrollTop = getScroll(element, 'top');
+  const scrollLeft = getScroll(element, 'left');
+  const modifier = subtract ? -1 : 1;
+  rect.top += scrollTop * modifier;
+  rect.bottom += scrollTop * modifier;
+  rect.left += scrollLeft * modifier;
+  rect.right += scrollLeft * modifier;
+  return rect;
+}
+
+/*
+ * Helper to detect borders of a given element
+ * @method
+ * @memberof Popper.Utils
+ * @param {CSSStyleDeclaration} styles
+ * Result of `getStyleComputedProperty` on the given element
+ * @param {String} axis - `x` or `y`
+ * @return {number} borders - The borders size of the given axis
+ */
+
+function getBordersSize(styles, axis) {
+  const sideA = axis === 'x' ? 'Left' : 'Top';
+  const sideB = sideA === 'Left' ? 'Right' : 'Bottom';
+
+  return parseFloat(styles[`border${sideA}Width`]) + parseFloat(styles[`border${sideB}Width`]);
+}
+
+function getSize(axis, body, html, computedStyle) {
+  return Math.max(body[`offset${axis}`], body[`scroll${axis}`], html[`client${axis}`], html[`offset${axis}`], html[`scroll${axis}`], isIE(10) ? parseInt(html[`offset${axis}`]) + parseInt(computedStyle[`margin${axis === 'Height' ? 'Top' : 'Left'}`]) + parseInt(computedStyle[`margin${axis === 'Height' ? 'Bottom' : 'Right'}`]) : 0);
+}
+
+function getWindowSizes(document) {
+  const body = document.body;
+  const html = document.documentElement;
+  const computedStyle = isIE(10) && getComputedStyle(html);
+
+  return {
+    height: getSize('Height', body, html, computedStyle),
+    width: getSize('Width', body, html, computedStyle)
+  };
+}
+
+var _extends = Object.assign || function (target) {
+  for (var i = 1; i < arguments.length; i++) {
+    var source = arguments[i];
+
+    for (var key in source) {
+      if (Object.prototype.hasOwnProperty.call(source, key)) {
+        target[key] = source[key];
+      }
+    }
+  }
+
+  return target;
+};
+
+/**
+ * Given element offsets, generate an output similar to getBoundingClientRect
+ * @method
+ * @memberof Popper.Utils
+ * @argument {Object} offsets
+ * @returns {Object} ClientRect like output
+ */
+function getClientRect(offsets) {
+  return _extends({}, offsets, {
+    right: offsets.left + offsets.width,
+    bottom: offsets.top + offsets.height
+  });
+}
+
+/**
+ * Get bounding client rect of given element
+ * @method
+ * @memberof Popper.Utils
+ * @param {HTMLElement} element
+ * @return {Object} client rect
+ */
+function getBoundingClientRect(element) {
+  let rect = {};
+
+  // IE10 10 FIX: Please, don't ask, the element isn't
+  // considered in DOM in some circumstances...
+  // This isn't reproducible in IE10 compatibility mode of IE11
+  try {
+    if (isIE(10)) {
+      rect = element.getBoundingClientRect();
+      const scrollTop = getScroll(element, 'top');
+      const scrollLeft = getScroll(element, 'left');
+      rect.top += scrollTop;
+      rect.left += scrollLeft;
+      rect.bottom += scrollTop;
+      rect.right += scrollLeft;
+    } else {
+      rect = element.getBoundingClientRect();
+    }
+  } catch (e) {}
+
+  const result = {
+    left: rect.left,
+    top: rect.top,
+    width: rect.right - rect.left,
+    height: rect.bottom - rect.top
+  };
+
+  // subtract scrollbar size from sizes
+  const sizes = element.nodeName === 'HTML' ? getWindowSizes(element.ownerDocument) : {};
+  const width = sizes.width || element.clientWidth || result.width;
+  const height = sizes.height || element.clientHeight || result.height;
+
+  let horizScrollbar = element.offsetWidth - width;
+  let vertScrollbar = element.offsetHeight - height;
+
+  // if an hypothetical scrollbar is detected, we must be sure it's not a `border`
+  // we make this check conditional for performance reasons
+  if (horizScrollbar || vertScrollbar) {
+    const styles = getStyleComputedProperty(element);
+    horizScrollbar -= getBordersSize(styles, 'x');
+    vertScrollbar -= getBordersSize(styles, 'y');
+
+    result.width -= horizScrollbar;
+    result.height -= vertScrollbar;
+  }
+
+  return getClientRect(result);
+}
+
+function getOffsetRectRelativeToArbitraryNode(children, parent, fixedPosition = false) {
+  const isIE10 = isIE(10);
+  const isHTML = parent.nodeName === 'HTML';
+  const childrenRect = getBoundingClientRect(children);
+  const parentRect = getBoundingClientRect(parent);
+  const scrollParent = getScrollParent(children);
+
+  const styles = getStyleComputedProperty(parent);
+  const borderTopWidth = parseFloat(styles.borderTopWidth);
+  const borderLeftWidth = parseFloat(styles.borderLeftWidth);
+
+  // In cases where the parent is fixed, we must ignore negative scroll in offset calc
+  if (fixedPosition && isHTML) {
+    parentRect.top = Math.max(parentRect.top, 0);
+    parentRect.left = Math.max(parentRect.left, 0);
+  }
+  let offsets = getClientRect({
+    top: childrenRect.top - parentRect.top - borderTopWidth,
+    left: childrenRect.left - parentRect.left - borderLeftWidth,
+    width: childrenRect.width,
+    height: childrenRect.height
+  });
+  offsets.marginTop = 0;
+  offsets.marginLeft = 0;
+
+  // Subtract margins of documentElement in case it's being used as parent
+  // we do this only on HTML because it's the only element that behaves
+  // differently when margins are applied to it. The margins are included in
+  // the box of the documentElement, in the other cases not.
+  if (!isIE10 && isHTML) {
+    const marginTop = parseFloat(styles.marginTop);
+    const marginLeft = parseFloat(styles.marginLeft);
+
+    offsets.top -= borderTopWidth - marginTop;
+    offsets.bottom -= borderTopWidth - marginTop;
+    offsets.left -= borderLeftWidth - marginLeft;
+    offsets.right -= borderLeftWidth - marginLeft;
+
+    // Attach marginTop and marginLeft because in some circumstances we may need them
+    offsets.marginTop = marginTop;
+    offsets.marginLeft = marginLeft;
+  }
+
+  if (isIE10 && !fixedPosition ? parent.contains(scrollParent) : parent === scrollParent && scrollParent.nodeName !== 'BODY') {
+    offsets = includeScroll(offsets, parent);
+  }
+
+  return offsets;
+}
+
+function getViewportOffsetRectRelativeToArtbitraryNode(element, excludeScroll = false) {
+  const html = element.ownerDocument.documentElement;
+  const relativeOffset = getOffsetRectRelativeToArbitraryNode(element, html);
+  const width = Math.max(html.clientWidth, window.innerWidth || 0);
+  const height = Math.max(html.clientHeight, window.innerHeight || 0);
+
+  const scrollTop = !excludeScroll ? getScroll(html) : 0;
+  const scrollLeft = !excludeScroll ? getScroll(html, 'left') : 0;
+
+  const offset = {
+    top: scrollTop - relativeOffset.top + relativeOffset.marginTop,
+    left: scrollLeft - relativeOffset.left + relativeOffset.marginLeft,
+    width,
+    height
+  };
+
+  return getClientRect(offset);
+}
+
+/**
+ * Check if the given element is fixed or is inside a fixed parent
+ * @method
+ * @memberof Popper.Utils
+ * @argument {Element} element
+ * @argument {Element} customContainer
+ * @returns {Boolean} answer to "isFixed?"
+ */
+function isFixed(element) {
+  const nodeName = element.nodeName;
+  if (nodeName === 'BODY' || nodeName === 'HTML') {
+    return false;
+  }
+  if (getStyleComputedProperty(element, 'position') === 'fixed') {
+    return true;
+  }
+  const parentNode = getParentNode(element);
+  if (!parentNode) {
+    return false;
+  }
+  return isFixed(parentNode);
+}
+
+/**
+ * Finds the first parent of an element that has a transformed property defined
+ * @method
+ * @memberof Popper.Utils
+ * @argument {Element} element
+ * @returns {Element} first transformed parent or documentElement
+ */
+
+function getFixedPositionOffsetParent(element) {
+  // This check is needed to avoid errors in case one of the elements isn't defined for any reason
+  if (!element || !element.parentElement || isIE()) {
+    return document.documentElement;
+  }
+  let el = element.parentElement;
+  while (el && getStyleComputedProperty(el, 'transform') === 'none') {
+    el = el.parentElement;
+  }
+  return el || document.documentElement;
+}
+
+/**
+ * Computed the boundaries limits and return them
+ * @method
+ * @memberof Popper.Utils
+ * @param {HTMLElement} popper
+ * @param {HTMLElement} reference
+ * @param {number} padding
+ * @param {HTMLElement} boundariesElement - Element used to define the boundaries
+ * @param {Boolean} fixedPosition - Is in fixed position mode
+ * @returns {Object} Coordinates of the boundaries
+ */
+function getBoundaries(popper, reference, padding, boundariesElement, fixedPosition = false) {
+  // NOTE: 1 DOM access here
+
+  let boundaries = { top: 0, left: 0 };
+  const offsetParent = fixedPosition ? getFixedPositionOffsetParent(popper) : findCommonOffsetParent(popper, getReferenceNode(reference));
+
+  // Handle viewport case
+  if (boundariesElement === 'viewport') {
+    boundaries = getViewportOffsetRectRelativeToArtbitraryNode(offsetParent, fixedPosition);
+  } else {
+    // Handle other cases based on DOM element used as boundaries
+    let boundariesNode;
+    if (boundariesElement === 'scrollParent') {
+      boundariesNode = getScrollParent(getParentNode(reference));
+      if (boundariesNode.nodeName === 'BODY') {
+        boundariesNode = popper.ownerDocument.documentElement;
+      }
+    } else if (boundariesElement === 'window') {
+      boundariesNode = popper.ownerDocument.documentElement;
+    } else {
+      boundariesNode = boundariesElement;
+    }
+
+    const offsets = getOffsetRectRelativeToArbitraryNode(boundariesNode, offsetParent, fixedPosition);
+
+    // In case of HTML, we need a different computation
+    if (boundariesNode.nodeName === 'HTML' && !isFixed(offsetParent)) {
+      const { height, width } = getWindowSizes(popper.ownerDocument);
+      boundaries.top += offsets.top - offsets.marginTop;
+      boundaries.bottom = height + offsets.top;
+      boundaries.left += offsets.left - offsets.marginLeft;
+      boundaries.right = width + offsets.left;
+    } else {
+      // for all the other DOM elements, this one is good
+      boundaries = offsets;
+    }
+  }
+
+  // Add paddings
+  padding = padding || 0;
+  const isPaddingNumber = typeof padding === 'number';
+  boundaries.left += isPaddingNumber ? padding : padding.left || 0;
+  boundaries.top += isPaddingNumber ? padding : padding.top || 0;
+  boundaries.right -= isPaddingNumber ? padding : padding.right || 0;
+  boundaries.bottom -= isPaddingNumber ? padding : padding.bottom || 0;
+
+  return boundaries;
+}
+
+function getArea({ width, height }) {
+  return width * height;
+}
+
+/**
+ * Utility used to transform the `auto` placement to the placement with more
+ * available space.
+ * @method
+ * @memberof Popper.Utils
+ * @argument {Object} data - The data object generated by update method
+ * @argument {Object} options - Modifiers configuration and options
+ * @returns {Object} The data object, properly modified
+ */
+function computeAutoPlacement(placement, refRect, popper, reference, boundariesElement, padding = 0) {
+  if (placement.indexOf('auto') === -1) {
+    return placement;
+  }
+
+  const boundaries = getBoundaries(popper, reference, padding, boundariesElement);
+
+  const rects = {
+    top: {
+      width: boundaries.width,
+      height: refRect.top - boundaries.top
+    },
+    right: {
+      width: boundaries.right - refRect.right,
+      height: boundaries.height
+    },
+    bottom: {
+      width: boundaries.width,
+      height: boundaries.bottom - refRect.bottom
+    },
+    left: {
+      width: refRect.left - boundaries.left,
+      height: boundaries.height
+    }
+  };
+
+  const sortedAreas = Object.keys(rects).map(key => _extends({
+    key
+  }, rects[key], {
+    area: getArea(rects[key])
+  })).sort((a, b) => b.area - a.area);
+
+  const filteredAreas = sortedAreas.filter(({ width, height }) => width >= popper.clientWidth && height >= popper.clientHeight);
+
+  const computedPlacement = filteredAreas.length > 0 ? filteredAreas[0].key : sortedAreas[0].key;
+
+  const variation = placement.split('-')[1];
+
+  return computedPlacement + (variation ? `-${variation}` : '');
+}
+
+/**
+ * Get offsets to the reference element
+ * @method
+ * @memberof Popper.Utils
+ * @param {Object} state
+ * @param {Element} popper - the popper element
+ * @param {Element} reference - the reference element (the popper will be relative to this)
+ * @param {Element} fixedPosition - is in fixed position mode
+ * @returns {Object} An object containing the offsets which will be applied to the popper
+ */
+function getReferenceOffsets(state, popper, reference, fixedPosition = null) {
+  const commonOffsetParent = fixedPosition ? getFixedPositionOffsetParent(popper) : findCommonOffsetParent(popper, getReferenceNode(reference));
+  return getOffsetRectRelativeToArbitraryNode(reference, commonOffsetParent, fixedPosition);
+}
+
+/**
+ * Get the outer sizes of the given element (offset size + margins)
+ * @method
+ * @memberof Popper.Utils
+ * @argument {Element} element
+ * @returns {Object} object containing width and height properties
+ */
+function getOuterSizes(element) {
+  const window = element.ownerDocument.defaultView;
+  const styles = window.getComputedStyle(element);
+  const x = parseFloat(styles.marginTop || 0) + parseFloat(styles.marginBottom || 0);
+  const y = parseFloat(styles.marginLeft || 0) + parseFloat(styles.marginRight || 0);
+  const result = {
+    width: element.offsetWidth + y,
+    height: element.offsetHeight + x
+  };
+  return result;
+}
+
+/**
+ * Get the opposite placement of the given one
+ * @method
+ * @memberof Popper.Utils
+ * @argument {String} placement
+ * @returns {String} flipped placement
+ */
+function getOppositePlacement(placement) {
+  const hash = { left: 'right', right: 'left', bottom: 'top', top: 'bottom' };
+  return placement.replace(/left|right|bottom|top/g, matched => hash[matched]);
+}
+
+/**
+ * Get offsets to the popper
+ * @method
+ * @memberof Popper.Utils
+ * @param {Object} position - CSS position the Popper will get applied
+ * @param {HTMLElement} popper - the popper element
+ * @param {Object} referenceOffsets - the reference offsets (the popper will be relative to this)
+ * @param {String} placement - one of the valid placement options
+ * @returns {Object} popperOffsets - An object containing the offsets which will be applied to the popper
+ */
+function getPopperOffsets(popper, referenceOffsets, placement) {
+  placement = placement.split('-')[0];
+
+  // Get popper node sizes
+  const popperRect = getOuterSizes(popper);
+
+  // Add position, width and height to our offsets object
+  const popperOffsets = {
+    width: popperRect.width,
+    height: popperRect.height
+  };
+
+  // depending by the popper placement we have to compute its offsets slightly differently
+  const isHoriz = ['right', 'left'].indexOf(placement) !== -1;
+  const mainSide = isHoriz ? 'top' : 'left';
+  const secondarySide = isHoriz ? 'left' : 'top';
+  const measurement = isHoriz ? 'height' : 'width';
+  const secondaryMeasurement = !isHoriz ? 'height' : 'width';
+
+  popperOffsets[mainSide] = referenceOffsets[mainSide] + referenceOffsets[measurement] / 2 - popperRect[measurement] / 2;
+  if (placement === secondarySide) {
+    popperOffsets[secondarySide] = referenceOffsets[secondarySide] - popperRect[secondaryMeasurement];
+  } else {
+    popperOffsets[secondarySide] = referenceOffsets[getOppositePlacement(secondarySide)];
+  }
+
+  return popperOffsets;
+}
+
+/**
+ * Mimics the `find` method of Array
+ * @method
+ * @memberof Popper.Utils
+ * @argument {Array} arr
+ * @argument prop
+ * @argument value
+ * @returns index or -1
+ */
+function find(arr, check) {
+  // use native find if supported
+  if (Array.prototype.find) {
+    return arr.find(check);
+  }
+
+  // use `filter` to obtain the same behavior of `find`
+  return arr.filter(check)[0];
+}
+
+/**
+ * Return the index of the matching object
+ * @method
+ * @memberof Popper.Utils
+ * @argument {Array} arr
+ * @argument prop
+ * @argument value
+ * @returns index or -1
+ */
+function findIndex(arr, prop, value) {
+  // use native findIndex if supported
+  if (Array.prototype.findIndex) {
+    return arr.findIndex(cur => cur[prop] === value);
+  }
+
+  // use `find` + `indexOf` if `findIndex` isn't supported
+  const match = find(arr, obj => obj[prop] === value);
+  return arr.indexOf(match);
+}
+
+/**
+ * Loop trough the list of modifiers and run them in order,
+ * each of them will then edit the data object.
+ * @method
+ * @memberof Popper.Utils
+ * @param {dataObject} data
+ * @param {Array} modifiers
+ * @param {String} ends - Optional modifier name used as stopper
+ * @returns {dataObject}
+ */
+function runModifiers(modifiers, data, ends) {
+  const modifiersToRun = ends === undefined ? modifiers : modifiers.slice(0, findIndex(modifiers, 'name', ends));
+
+  modifiersToRun.forEach(modifier => {
+    if (modifier['function']) {
+      // eslint-disable-line dot-notation
+      console.warn('`modifier.function` is deprecated, use `modifier.fn`!');
+    }
+    const fn = modifier['function'] || modifier.fn; // eslint-disable-line dot-notation
+    if (modifier.enabled && isFunction(fn)) {
+      // Add properties to offsets to make them a complete clientRect object
+      // we do this before each modifier to make sure the previous one doesn't
+      // mess with these values
+      data.offsets.popper = getClientRect(data.offsets.popper);
+      data.offsets.reference = getClientRect(data.offsets.reference);
+
+      data = fn(data, modifier);
+    }
+  });
+
+  return data;
+}
+
+/**
+ * Updates the position of the popper, computing the new offsets and applying
+ * the new style.<br />
+ * Prefer `scheduleUpdate` over `update` because of performance reasons.
+ * @method
+ * @memberof Popper
+ */
+function update() {
+  // if popper is destroyed, don't perform any further update
+  if (this.state.isDestroyed) {
+    return;
+  }
+
+  let data = {
+    instance: this,
+    styles: {},
+    arrowStyles: {},
+    attributes: {},
+    flipped: false,
+    offsets: {}
+  };
+
+  // compute reference element offsets
+  data.offsets.reference = getReferenceOffsets(this.state, this.popper, this.reference, this.options.positionFixed);
+
+  // compute auto placement, store placement inside the data object,
+  // modifiers will be able to edit `placement` if needed
+  // and refer to originalPlacement to know the original value
+  data.placement = computeAutoPlacement(this.options.placement, data.offsets.reference, this.popper, this.reference, this.options.modifiers.flip.boundariesElement, this.options.modifiers.flip.padding);
+
+  // store the computed placement inside `originalPlacement`
+  data.originalPlacement = data.placement;
+
+  data.positionFixed = this.options.positionFixed;
+
+  // compute the popper offsets
+  data.offsets.popper = getPopperOffsets(this.popper, data.offsets.reference, data.placement);
+
+  data.offsets.popper.position = this.options.positionFixed ? 'fixed' : 'absolute';
+
+  // run the modifiers
+  data = runModifiers(this.modifiers, data);
+
+  // the first `update` will call `onCreate` callback
+  // the other ones will call `onUpdate` callback
+  if (!this.state.isCreated) {
+    this.state.isCreated = true;
+    this.options.onCreate(data);
+  } else {
+    this.options.onUpdate(data);
+  }
+}
+
+/**
+ * Helper used to know if the given modifier is enabled.
+ * @method
+ * @memberof Popper.Utils
+ * @returns {Boolean}
+ */
+function isModifierEnabled(modifiers, modifierName) {
+  return modifiers.some(({ name, enabled }) => enabled && name === modifierName);
+}
+
+/**
+ * Get the prefixed supported property name
+ * @method
+ * @memberof Popper.Utils
+ * @argument {String} property (camelCase)
+ * @returns {String} prefixed property (camelCase or PascalCase, depending on the vendor prefix)
+ */
+function getSupportedPropertyName(property) {
+  const prefixes = [false, 'ms', 'Webkit', 'Moz', 'O'];
+  const upperProp = property.charAt(0).toUpperCase() + property.slice(1);
+
+  for (let i = 0; i < prefixes.length; i++) {
+    const prefix = prefixes[i];
+    const toCheck = prefix ? `${prefix}${upperProp}` : property;
+    if (typeof document.body.style[toCheck] !== 'undefined') {
+      return toCheck;
+    }
+  }
+  return null;
+}
+
+/**
+ * Destroys the popper.
+ * @method
+ * @memberof Popper
+ */
+function destroy() {
+  this.state.isDestroyed = true;
+
+  // touch DOM only if `applyStyle` modifier is enabled
+  if (isModifierEnabled(this.modifiers, 'applyStyle')) {
+    this.popper.removeAttribute('x-placement');
+    this.popper.style.position = '';
+    this.popper.style.top = '';
+    this.popper.style.left = '';
+    this.popper.style.right = '';
+    this.popper.style.bottom = '';
+    this.popper.style.willChange = '';
+    this.popper.style[getSupportedPropertyName('transform')] = '';
+  }
+
+  this.disableEventListeners();
+
+  // remove the popper if user explicitly asked for the deletion on destroy
+  // do not use `remove` because IE11 doesn't support it
+  if (this.options.removeOnDestroy) {
+    this.popper.parentNode.removeChild(this.popper);
+  }
+  return this;
+}
+
+/**
+ * Get the window associated with the element
+ * @argument {Element} element
+ * @returns {Window}
+ */
+function getWindow(element) {
+  const ownerDocument = element.ownerDocument;
+  return ownerDocument ? ownerDocument.defaultView : window;
+}
+
+function attachToScrollParents(scrollParent, event, callback, scrollParents) {
+  const isBody = scrollParent.nodeName === 'BODY';
+  const target = isBody ? scrollParent.ownerDocument.defaultView : scrollParent;
+  target.addEventListener(event, callback, { passive: true });
+
+  if (!isBody) {
+    attachToScrollParents(getScrollParent(target.parentNode), event, callback, scrollParents);
+  }
+  scrollParents.push(target);
+}
+
+/**
+ * Setup needed event listeners used to update the popper position
+ * @method
+ * @memberof Popper.Utils
+ * @private
+ */
+function setupEventListeners(reference, options, state, updateBound) {
+  // Resize event listener on window
+  state.updateBound = updateBound;
+  getWindow(reference).addEventListener('resize', state.updateBound, { passive: true });
+
+  // Scroll event listener on scroll parents
+  const scrollElement = getScrollParent(reference);
+  attachToScrollParents(scrollElement, 'scroll', state.updateBound, state.scrollParents);
+  state.scrollElement = scrollElement;
+  state.eventsEnabled = true;
+
+  return state;
+}
+
+/**
+ * It will add resize/scroll events and start recalculating
+ * position of the popper element when they are triggered.
+ * @method
+ * @memberof Popper
+ */
+function enableEventListeners() {
+  if (!this.state.eventsEnabled) {
+    this.state = setupEventListeners(this.reference, this.options, this.state, this.scheduleUpdate);
+  }
+}
+
+/**
+ * Remove event listeners used to update the popper position
+ * @method
+ * @memberof Popper.Utils
+ * @private
+ */
+function removeEventListeners(reference, state) {
+  // Remove resize event listener on window
+  getWindow(reference).removeEventListener('resize', state.updateBound);
+
+  // Remove scroll event listener on scroll parents
+  state.scrollParents.forEach(target => {
+    target.removeEventListener('scroll', state.updateBound);
+  });
+
+  // Reset state
+  state.updateBound = null;
+  state.scrollParents = [];
+  state.scrollElement = null;
+  state.eventsEnabled = false;
+  return state;
+}
+
+/**
+ * It will remove resize/scroll events and won't recalculate popper position
+ * when they are triggered. It also won't trigger `onUpdate` callback anymore,
+ * unless you call `update` method manually.
+ * @method
+ * @memberof Popper
+ */
+function disableEventListeners() {
+  if (this.state.eventsEnabled) {
+    cancelAnimationFrame(this.scheduleUpdate);
+    this.state = removeEventListeners(this.reference, this.state);
+  }
+}
+
+/**
+ * Tells if a given input is a number
+ * @method
+ * @memberof Popper.Utils
+ * @param {*} input to check
+ * @return {Boolean}
+ */
+function isNumeric(n) {
+  return n !== '' && !isNaN(parseFloat(n)) && isFinite(n);
+}
+
+/**
+ * Set the style to the given popper
+ * @method
+ * @memberof Popper.Utils
+ * @argument {Element} element - Element to apply the style to
+ * @argument {Object} styles
+ * Object with a list of properties and values which will be applied to the element
+ */
+function setStyles(element, styles) {
+  Object.keys(styles).forEach(prop => {
+    let unit = '';
+    // add unit if the value is numeric and is one of the following
+    if (['width', 'height', 'top', 'right', 'bottom', 'left'].indexOf(prop) !== -1 && isNumeric(styles[prop])) {
+      unit = 'px';
+    }
+    element.style[prop] = styles[prop] + unit;
+  });
+}
+
+/**
+ * Set the attributes to the given popper
+ * @method
+ * @memberof Popper.Utils
+ * @argument {Element} element - Element to apply the attributes to
+ * @argument {Object} styles
+ * Object with a list of properties and values which will be applied to the element
+ */
+function setAttributes(element, attributes) {
+  Object.keys(attributes).forEach(function (prop) {
+    const value = attributes[prop];
+    if (value !== false) {
+      element.setAttribute(prop, attributes[prop]);
+    } else {
+      element.removeAttribute(prop);
+    }
+  });
+}
+
+/**
+ * @function
+ * @memberof Modifiers
+ * @argument {Object} data - The data object generated by `update` method
+ * @argument {Object} data.styles - List of style properties - values to apply to popper element
+ * @argument {Object} data.attributes - List of attribute properties - values to apply to popper element
+ * @argument {Object} options - Modifiers configuration and options
+ * @returns {Object} The same data object
+ */
+function applyStyle(data) {
+  // any property present in `data.styles` will be applied to the popper,
+  // in this way we can make the 3rd party modifiers add custom styles to it
+  // Be aware, modifiers could override the properties defined in the previous
+  // lines of this modifier!
+  setStyles(data.instance.popper, data.styles);
+
+  // any property present in `data.attributes` will be applied to the popper,
+  // they will be set as HTML attributes of the element
+  setAttributes(data.instance.popper, data.attributes);
+
+  // if arrowElement is defined and arrowStyles has some properties
+  if (data.arrowElement && Object.keys(data.arrowStyles).length) {
+    setStyles(data.arrowElement, data.arrowStyles);
+  }
+
+  return data;
+}
+
+/**
+ * Set the x-placement attribute before everything else because it could be used
+ * to add margins to the popper margins needs to be calculated to get the
+ * correct popper offsets.
+ * @method
+ * @memberof Popper.modifiers
+ * @param {HTMLElement} reference - The reference element used to position the popper
+ * @param {HTMLElement} popper - The HTML element used as popper
+ * @param {Object} options - Popper.js options
+ */
+function applyStyleOnLoad(reference, popper, options, modifierOptions, state) {
+  // compute reference element offsets
+  const referenceOffsets = getReferenceOffsets(state, popper, reference, options.positionFixed);
+
+  // compute auto placement, store placement inside the data object,
+  // modifiers will be able to edit `placement` if needed
+  // and refer to originalPlacement to know the original value
+  const placement = computeAutoPlacement(options.placement, referenceOffsets, popper, reference, options.modifiers.flip.boundariesElement, options.modifiers.flip.padding);
+
+  popper.setAttribute('x-placement', placement);
+
+  // Apply `position` to popper before anything else because
+  // without the position applied we can't guarantee correct computations
+  setStyles(popper, { position: options.positionFixed ? 'fixed' : 'absolute' });
+
+  return options;
+}
+
+/**
+ * @function
+ * @memberof Popper.Utils
+ * @argument {Object} data - The data object generated by `update` method
+ * @argument {Boolean} shouldRound - If the offsets should be rounded at all
+ * @returns {Object} The popper's position offsets rounded
+ *
+ * The tale of pixel-perfect positioning. It's still not 100% perfect, but as
+ * good as it can be within reason.
+ * Discussion here: https://github.com/FezVrasta/popper.js/pull/715
+ *
+ * Low DPI screens cause a popper to be blurry if not using full pixels (Safari
+ * as well on High DPI screens).
+ *
+ * Firefox prefers no rounding for positioning and does not have blurriness on
+ * high DPI screens.
+ *
+ * Only horizontal placement and left/right values need to be considered.
+ */
+function getRoundedOffsets(data, shouldRound) {
+  const { popper, reference } = data.offsets;
+  const { round, floor } = Math;
+  const noRound = v => v;
+
+  const referenceWidth = round(reference.width);
+  const popperWidth = round(popper.width);
+
+  const isVertical = ['left', 'right'].indexOf(data.placement) !== -1;
+  const isVariation = data.placement.indexOf('-') !== -1;
+  const sameWidthParity = referenceWidth % 2 === popperWidth % 2;
+  const bothOddWidth = referenceWidth % 2 === 1 && popperWidth % 2 === 1;
+
+  const horizontalToInteger = !shouldRound ? noRound : isVertical || isVariation || sameWidthParity ? round : floor;
+  const verticalToInteger = !shouldRound ? noRound : round;
+
+  return {
+    left: horizontalToInteger(bothOddWidth && !isVariation && shouldRound ? popper.left - 1 : popper.left),
+    top: verticalToInteger(popper.top),
+    bottom: verticalToInteger(popper.bottom),
+    right: horizontalToInteger(popper.right)
+  };
+}
+
+const isFirefox = isBrowser && /Firefox/i.test(navigator.userAgent);
+
+/**
+ * @function
+ * @memberof Modifiers
+ * @argument {Object} data - The data object generated by `update` method
+ * @argument {Object} options - Modifiers configuration and options
+ * @returns {Object} The data object, properly modified
+ */
+function computeStyle(data, options) {
+  const { x, y } = options;
+  const { popper } = data.offsets;
+
+  // Remove this legacy support in Popper.js v2
+  const legacyGpuAccelerationOption = find(data.instance.modifiers, modifier => modifier.name === 'applyStyle').gpuAcceleration;
+  if (legacyGpuAccelerationOption !== undefined) {
+    console.warn('WARNING: `gpuAcceleration` option moved to `computeStyle` modifier and will not be supported in future versions of Popper.js!');
+  }
+  const gpuAcceleration = legacyGpuAccelerationOption !== undefined ? legacyGpuAccelerationOption : options.gpuAcceleration;
+
+  const offsetParent = getOffsetParent(data.instance.popper);
+  const offsetParentRect = getBoundingClientRect(offsetParent);
+
+  // Styles
+  const styles = {
+    position: popper.position
+  };
+
+  const offsets = getRoundedOffsets(data, window.devicePixelRatio < 2 || !isFirefox);
+
+  const sideA = x === 'bottom' ? 'top' : 'bottom';
+  const sideB = y === 'right' ? 'left' : 'right';
+
+  // if gpuAcceleration is set to `true` and transform is supported,
+  //  we use `translate3d` to apply the position to the popper we
+  // automatically use the supported prefixed version if needed
+  const prefixedProperty = getSupportedPropertyName('transform');
+
+  // now, let's make a step back and look at this code closely (wtf?)
+  // If the content of the popper grows once it's been positioned, it
+  // may happen that the popper gets misplaced because of the new content
+  // overflowing its reference element
+  // To avoid this problem, we provide two options (x and y), which allow
+  // the consumer to define the offset origin.
+  // If we position a popper on top of a reference element, we can set
+  // `x` to `top` to make the popper grow towards its top instead of
+  // its bottom.
+  let left, top;
+  if (sideA === 'bottom') {
+    // when offsetParent is <html> the positioning is relative to the bottom of the screen (excluding the scrollbar)
+    // and not the bottom of the html element
+    if (offsetParent.nodeName === 'HTML') {
+      top = -offsetParent.clientHeight + offsets.bottom;
+    } else {
+      top = -offsetParentRect.height + offsets.bottom;
+    }
+  } else {
+    top = offsets.top;
+  }
+  if (sideB === 'right') {
+    if (offsetParent.nodeName === 'HTML') {
+      left = -offsetParent.clientWidth + offsets.right;
+    } else {
+      left = -offsetParentRect.width + offsets.right;
+    }
+  } else {
+    left = offsets.left;
+  }
+  if (gpuAcceleration && prefixedProperty) {
+    styles[prefixedProperty] = `translate3d(${left}px, ${top}px, 0)`;
+    styles[sideA] = 0;
+    styles[sideB] = 0;
+    styles.willChange = 'transform';
+  } else {
+    // othwerise, we use the standard `top`, `left`, `bottom` and `right` properties
+    const invertTop = sideA === 'bottom' ? -1 : 1;
+    const invertLeft = sideB === 'right' ? -1 : 1;
+    styles[sideA] = top * invertTop;
+    styles[sideB] = left * invertLeft;
+    styles.willChange = `${sideA}, ${sideB}`;
+  }
+
+  // Attributes
+  const attributes = {
+    'x-placement': data.placement
+  };
+
+  // Update `data` attributes, styles and arrowStyles
+  data.attributes = _extends({}, attributes, data.attributes);
+  data.styles = _extends({}, styles, data.styles);
+  data.arrowStyles = _extends({}, data.offsets.arrow, data.arrowStyles);
+
+  return data;
+}
+
+/**
+ * Helper used to know if the given modifier depends from another one.<br />
+ * It checks if the needed modifier is listed and enabled.
+ * @method
+ * @memberof Popper.Utils
+ * @param {Array} modifiers - list of modifiers
+ * @param {String} requestingName - name of requesting modifier
+ * @param {String} requestedName - name of requested modifier
+ * @returns {Boolean}
+ */
+function isModifierRequired(modifiers, requestingName, requestedName) {
+  const requesting = find(modifiers, ({ name }) => name === requestingName);
+
+  const isRequired = !!requesting && modifiers.some(modifier => {
+    return modifier.name === requestedName && modifier.enabled && modifier.order < requesting.order;
+  });
+
+  if (!isRequired) {
+    const requesting = `\`${requestingName}\``;
+    const requested = `\`${requestedName}\``;
+    console.warn(`${requested} modifier is required by ${requesting} modifier in order to work, be sure to include it before ${requesting}!`);
+  }
+  return isRequired;
+}
+
+/**
+ * @function
+ * @memberof Modifiers
+ * @argument {Object} data - The data object generated by update method
+ * @argument {Object} options - Modifiers configuration and options
+ * @returns {Object} The data object, properly modified
+ */
+function arrow(data, options) {
+  // arrow depends on keepTogether in order to work
+  if (!isModifierRequired(data.instance.modifiers, 'arrow', 'keepTogether')) {
+    return data;
+  }
+
+  let arrowElement = options.element;
+
+  // if arrowElement is a string, suppose it's a CSS selector
+  if (typeof arrowElement === 'string') {
+    arrowElement = data.instance.popper.querySelector(arrowElement);
+
+    // if arrowElement is not found, don't run the modifier
+    if (!arrowElement) {
+      return data;
+    }
+  } else {
+    // if the arrowElement isn't a query selector we must check that the
+    // provided DOM node is child of its popper node
+    if (!data.instance.popper.contains(arrowElement)) {
+      console.warn('WARNING: `arrow.element` must be child of its popper element!');
+      return data;
+    }
+  }
+
+  const placement = data.placement.split('-')[0];
+  const { popper, reference } = data.offsets;
+  const isVertical = ['left', 'right'].indexOf(placement) !== -1;
+
+  const len = isVertical ? 'height' : 'width';
+  const sideCapitalized = isVertical ? 'Top' : 'Left';
+  const side = sideCapitalized.toLowerCase();
+  const altSide = isVertical ? 'left' : 'top';
+  const opSide = isVertical ? 'bottom' : 'right';
+  const arrowElementSize = getOuterSizes(arrowElement)[len];
+
+  //
+  // extends keepTogether behavior making sure the popper and its
+  // reference have enough pixels in conjunction
+  //
+
+  // top/left side
+  if (reference[opSide] - arrowElementSize < popper[side]) {
+    data.offsets.popper[side] -= popper[side] - (reference[opSide] - arrowElementSize);
+  }
+  // bottom/right side
+  if (reference[side] + arrowElementSize > popper[opSide]) {
+    data.offsets.popper[side] += reference[side] + arrowElementSize - popper[opSide];
+  }
+  data.offsets.popper = getClientRect(data.offsets.popper);
+
+  // compute center of the popper
+  const center = reference[side] + reference[len] / 2 - arrowElementSize / 2;
+
+  // Compute the sideValue using the updated popper offsets
+  // take popper margin in account because we don't have this info available
+  const css = getStyleComputedProperty(data.instance.popper);
+  const popperMarginSide = parseFloat(css[`margin${sideCapitalized}`]);
+  const popperBorderSide = parseFloat(css[`border${sideCapitalized}Width`]);
+  let sideValue = center - data.offsets.popper[side] - popperMarginSide - popperBorderSide;
+
+  // prevent arrowElement from being placed not contiguously to its popper
+  sideValue = Math.max(Math.min(popper[len] - arrowElementSize, sideValue), 0);
+
+  data.arrowElement = arrowElement;
+  data.offsets.arrow = {
+    [side]: Math.round(sideValue),
+    [altSide]: '' // make sure to unset any eventual altSide value from the DOM node
+  };
+
+  return data;
+}
+
+/**
+ * Get the opposite placement variation of the given one
+ * @method
+ * @memberof Popper.Utils
+ * @argument {String} placement variation
+ * @returns {String} flipped placement variation
+ */
+function getOppositeVariation(variation) {
+  if (variation === 'end') {
+    return 'start';
+  } else if (variation === 'start') {
+    return 'end';
+  }
+  return variation;
+}
+
+/**
+ * List of accepted placements to use as values of the `placement` option.<br />
+ * Valid placements are:
+ * - `auto`
+ * - `top`
+ * - `right`
+ * - `bottom`
+ * - `left`
+ *
+ * Each placement can have a variation from this list:
+ * - `-start`
+ * - `-end`
+ *
+ * Variations are interpreted easily if you think of them as the left to right
+ * written languages. Horizontally (`top` and `bottom`), `start` is left and `end`
+ * is right.<br />
+ * Vertically (`left` and `right`), `start` is top and `end` is bottom.
+ *
+ * Some valid examples are:
+ * - `top-end` (on top of reference, right aligned)
+ * - `right-start` (on right of reference, top aligned)
+ * - `bottom` (on bottom, centered)
+ * - `auto-end` (on the side with more space available, alignment depends by placement)
+ *
+ * @static
+ * @type {Array}
+ * @enum {String}
+ * @readonly
+ * @method placements
+ * @memberof Popper
+ */
+var placements = ['auto-start', 'auto', 'auto-end', 'top-start', 'top', 'top-end', 'right-start', 'right', 'right-end', 'bottom-end', 'bottom', 'bottom-start', 'left-end', 'left', 'left-start'];
+
+// Get rid of `auto` `auto-start` and `auto-end`
+const validPlacements = placements.slice(3);
+
+/**
+ * Given an initial placement, returns all the subsequent placements
+ * clockwise (or counter-clockwise).
+ *
+ * @method
+ * @memberof Popper.Utils
+ * @argument {String} placement - A valid placement (it accepts variations)
+ * @argument {Boolean} counter - Set to true to walk the placements counterclockwise
+ * @returns {Array} placements including their variations
+ */
+function clockwise(placement, counter = false) {
+  const index = validPlacements.indexOf(placement);
+  const arr = validPlacements.slice(index + 1).concat(validPlacements.slice(0, index));
+  return counter ? arr.reverse() : arr;
+}
+
+const BEHAVIORS = {
+  FLIP: 'flip',
+  CLOCKWISE: 'clockwise',
+  COUNTERCLOCKWISE: 'counterclockwise'
+};
+
+/**
+ * @function
+ * @memberof Modifiers
+ * @argument {Object} data - The data object generated by update method
+ * @argument {Object} options - Modifiers configuration and options
+ * @returns {Object} The data object, properly modified
+ */
+function flip(data, options) {
+  // if `inner` modifier is enabled, we can't use the `flip` modifier
+  if (isModifierEnabled(data.instance.modifiers, 'inner')) {
+    return data;
+  }
+
+  if (data.flipped && data.placement === data.originalPlacement) {
+    // seems like flip is trying to loop, probably there's not enough space on any of the flippable sides
+    return data;
+  }
+
+  const boundaries = getBoundaries(data.instance.popper, data.instance.reference, options.padding, options.boundariesElement, data.positionFixed);
+
+  let placement = data.placement.split('-')[0];
+  let placementOpposite = getOppositePlacement(placement);
+  let variation = data.placement.split('-')[1] || '';
+
+  let flipOrder = [];
+
+  switch (options.behavior) {
+    case BEHAVIORS.FLIP:
+      flipOrder = [placement, placementOpposite];
+      break;
+    case BEHAVIORS.CLOCKWISE:
+      flipOrder = clockwise(placement);
+      break;
+    case BEHAVIORS.COUNTERCLOCKWISE:
+      flipOrder = clockwise(placement, true);
+      break;
+    default:
+      flipOrder = options.behavior;
+  }
+
+  flipOrder.forEach((step, index) => {
+    if (placement !== step || flipOrder.length === index + 1) {
+      return data;
+    }
+
+    placement = data.placement.split('-')[0];
+    placementOpposite = getOppositePlacement(placement);
+
+    const popperOffsets = data.offsets.popper;
+    const refOffsets = data.offsets.reference;
+
+    // using floor because the reference offsets may contain decimals we are not going to consider here
+    const floor = Math.floor;
+    const overlapsRef = placement === 'left' && floor(popperOffsets.right) > floor(refOffsets.left) || placement === 'right' && floor(popperOffsets.left) < floor(refOffsets.right) || placement === 'top' && floor(popperOffsets.bottom) > floor(refOffsets.top) || placement === 'bottom' && floor(popperOffsets.top) < floor(refOffsets.bottom);
+
+    const overflowsLeft = floor(popperOffsets.left) < floor(boundaries.left);
+    const overflowsRight = floor(popperOffsets.right) > floor(boundaries.right);
+    const overflowsTop = floor(popperOffsets.top) < floor(boundaries.top);
+    const overflowsBottom = floor(popperOffsets.bottom) > floor(boundaries.bottom);
+
+    const overflowsBoundaries = placement === 'left' && overflowsLeft || placement === 'right' && overflowsRight || placement === 'top' && overflowsTop || placement === 'bottom' && overflowsBottom;
+
+    // flip the variation if required
+    const isVertical = ['top', 'bottom'].indexOf(placement) !== -1;
+
+    // flips variation if reference element overflows boundaries
+    const flippedVariationByRef = !!options.flipVariations && (isVertical && variation === 'start' && overflowsLeft || isVertical && variation === 'end' && overflowsRight || !isVertical && variation === 'start' && overflowsTop || !isVertical && variation === 'end' && overflowsBottom);
+
+    // flips variation if popper content overflows boundaries
+    const flippedVariationByContent = !!options.flipVariationsByContent && (isVertical && variation === 'start' && overflowsRight || isVertical && variation === 'end' && overflowsLeft || !isVertical && variation === 'start' && overflowsBottom || !isVertical && variation === 'end' && overflowsTop);
+
+    const flippedVariation = flippedVariationByRef || flippedVariationByContent;
+
+    if (overlapsRef || overflowsBoundaries || flippedVariation) {
+      // this boolean to detect any flip loop
+      data.flipped = true;
+
+      if (overlapsRef || overflowsBoundaries) {
+        placement = flipOrder[index + 1];
+      }
+
+      if (flippedVariation) {
+        variation = getOppositeVariation(variation);
+      }
+
+      data.placement = placement + (variation ? '-' + variation : '');
+
+      // this object contains `position`, we want to preserve it along with
+      // any additional property we may add in the future
+      data.offsets.popper = _extends({}, data.offsets.popper, getPopperOffsets(data.instance.popper, data.offsets.reference, data.placement));
+
+      data = runModifiers(data.instance.modifiers, data, 'flip');
+    }
+  });
+  return data;
+}
+
+/**
+ * @function
+ * @memberof Modifiers
+ * @argument {Object} data - The data object generated by update method
+ * @argument {Object} options - Modifiers configuration and options
+ * @returns {Object} The data object, properly modified
+ */
+function keepTogether(data) {
+  const { popper, reference } = data.offsets;
+  const placement = data.placement.split('-')[0];
+  const floor = Math.floor;
+  const isVertical = ['top', 'bottom'].indexOf(placement) !== -1;
+  const side = isVertical ? 'right' : 'bottom';
+  const opSide = isVertical ? 'left' : 'top';
+  const measurement = isVertical ? 'width' : 'height';
+
+  if (popper[side] < floor(reference[opSide])) {
+    data.offsets.popper[opSide] = floor(reference[opSide]) - popper[measurement];
+  }
+  if (popper[opSide] > floor(reference[side])) {
+    data.offsets.popper[opSide] = floor(reference[side]);
+  }
+
+  return data;
+}
+
+/**
+ * Converts a string containing value + unit into a px value number
+ * @function
+ * @memberof {modifiers~offset}
+ * @private
+ * @argument {String} str - Value + unit string
+ * @argument {String} measurement - `height` or `width`
+ * @argument {Object} popperOffsets
+ * @argument {Object} referenceOffsets
+ * @returns {Number|String}
+ * Value in pixels, or original string if no values were extracted
+ */
+function toValue(str, measurement, popperOffsets, referenceOffsets) {
+  // separate value from unit
+  const split = str.match(/((?:\-|\+)?\d*\.?\d*)(.*)/);
+  const value = +split[1];
+  const unit = split[2];
+
+  // If it's not a number it's an operator, I guess
+  if (!value) {
+    return str;
+  }
+
+  if (unit.indexOf('%') === 0) {
+    let element;
+    switch (unit) {
+      case '%p':
+        element = popperOffsets;
+        break;
+      case '%':
+      case '%r':
+      default:
+        element = referenceOffsets;
+    }
+
+    const rect = getClientRect(element);
+    return rect[measurement] / 100 * value;
+  } else if (unit === 'vh' || unit === 'vw') {
+    // if is a vh or vw, we calculate the size based on the viewport
+    let size;
+    if (unit === 'vh') {
+      size = Math.max(document.documentElement.clientHeight, window.innerHeight || 0);
+    } else {
+      size = Math.max(document.documentElement.clientWidth, window.innerWidth || 0);
+    }
+    return size / 100 * value;
+  } else {
+    // if is an explicit pixel unit, we get rid of the unit and keep the value
+    // if is an implicit unit, it's px, and we return just the value
+    return value;
+  }
+}
+
+/**
+ * Parse an `offset` string to extrapolate `x` and `y` numeric offsets.
+ * @function
+ * @memberof {modifiers~offset}
+ * @private
+ * @argument {String} offset
+ * @argument {Object} popperOffsets
+ * @argument {Object} referenceOffsets
+ * @argument {String} basePlacement
+ * @returns {Array} a two cells array with x and y offsets in numbers
+ */
+function parseOffset(offset, popperOffsets, referenceOffsets, basePlacement) {
+  const offsets = [0, 0];
+
+  // Use height if placement is left or right and index is 0 otherwise use width
+  // in this way the first offset will use an axis and the second one
+  // will use the other one
+  const useHeight = ['right', 'left'].indexOf(basePlacement) !== -1;
+
+  // Split the offset string to obtain a list of values and operands
+  // The regex addresses values with the plus or minus sign in front (+10, -20, etc)
+  const fragments = offset.split(/(\+|\-)/).map(frag => frag.trim());
+
+  // Detect if the offset string contains a pair of values or a single one
+  // they could be separated by comma or space
+  const divider = fragments.indexOf(find(fragments, frag => frag.search(/,|\s/) !== -1));
+
+  if (fragments[divider] && fragments[divider].indexOf(',') === -1) {
+    console.warn('Offsets separated by white space(s) are deprecated, use a comma (,) instead.');
+  }
+
+  // If divider is found, we divide the list of values and operands to divide
+  // them by ofset X and Y.
+  const splitRegex = /\s*,\s*|\s+/;
+  let ops = divider !== -1 ? [fragments.slice(0, divider).concat([fragments[divider].split(splitRegex)[0]]), [fragments[divider].split(splitRegex)[1]].concat(fragments.slice(divider + 1))] : [fragments];
+
+  // Convert the values with units to absolute pixels to allow our computations
+  ops = ops.map((op, index) => {
+    // Most of the units rely on the orientation of the popper
+    const measurement = (index === 1 ? !useHeight : useHeight) ? 'height' : 'width';
+    let mergeWithPrevious = false;
+    return op
+    // This aggregates any `+` or `-` sign that aren't considered operators
+    // e.g.: 10 + +5 => [10, +, +5]
+    .reduce((a, b) => {
+      if (a[a.length - 1] === '' && ['+', '-'].indexOf(b) !== -1) {
+        a[a.length - 1] = b;
+        mergeWithPrevious = true;
+        return a;
+      } else if (mergeWithPrevious) {
+        a[a.length - 1] += b;
+        mergeWithPrevious = false;
+        return a;
+      } else {
+        return a.concat(b);
+      }
+    }, [])
+    // Here we convert the string values into number values (in px)
+    .map(str => toValue(str, measurement, popperOffsets, referenceOffsets));
+  });
+
+  // Loop trough the offsets arrays and execute the operations
+  ops.forEach((op, index) => {
+    op.forEach((frag, index2) => {
+      if (isNumeric(frag)) {
+        offsets[index] += frag * (op[index2 - 1] === '-' ? -1 : 1);
+      }
+    });
+  });
+  return offsets;
+}
+
+/**
+ * @function
+ * @memberof Modifiers
+ * @argument {Object} data - The data object generated by update method
+ * @argument {Object} options - Modifiers configuration and options
+ * @argument {Number|String} options.offset=0
+ * The offset value as described in the modifier description
+ * @returns {Object} The data object, properly modified
+ */
+function offset(data, { offset }) {
+  const { placement, offsets: { popper, reference } } = data;
+  const basePlacement = placement.split('-')[0];
+
+  let offsets;
+  if (isNumeric(+offset)) {
+    offsets = [+offset, 0];
+  } else {
+    offsets = parseOffset(offset, popper, reference, basePlacement);
+  }
+
+  if (basePlacement === 'left') {
+    popper.top += offsets[0];
+    popper.left -= offsets[1];
+  } else if (basePlacement === 'right') {
+    popper.top += offsets[0];
+    popper.left += offsets[1];
+  } else if (basePlacement === 'top') {
+    popper.left += offsets[0];
+    popper.top -= offsets[1];
+  } else if (basePlacement === 'bottom') {
+    popper.left += offsets[0];
+    popper.top += offsets[1];
+  }
+
+  data.popper = popper;
+  return data;
+}
+
+/**
+ * @function
+ * @memberof Modifiers
+ * @argument {Object} data - The data object generated by `update` method
+ * @argument {Object} options - Modifiers configuration and options
+ * @returns {Object} The data object, properly modified
+ */
+function preventOverflow(data, options) {
+  let boundariesElement = options.boundariesElement || getOffsetParent(data.instance.popper);
+
+  // If offsetParent is the reference element, we really want to
+  // go one step up and use the next offsetParent as reference to
+  // avoid to make this modifier completely useless and look like broken
+  if (data.instance.reference === boundariesElement) {
+    boundariesElement = getOffsetParent(boundariesElement);
+  }
+
+  // NOTE: DOM access here
+  // resets the popper's position so that the document size can be calculated excluding
+  // the size of the popper element itself
+  const transformProp = getSupportedPropertyName('transform');
+  const popperStyles = data.instance.popper.style; // assignment to help minification
+  const { top, left, [transformProp]: transform } = popperStyles;
+  popperStyles.top = '';
+  popperStyles.left = '';
+  popperStyles[transformProp] = '';
+
+  const boundaries = getBoundaries(data.instance.popper, data.instance.reference, options.padding, boundariesElement, data.positionFixed);
+
+  // NOTE: DOM access here
+  // restores the original style properties after the offsets have been computed
+  popperStyles.top = top;
+  popperStyles.left = left;
+  popperStyles[transformProp] = transform;
+
+  options.boundaries = boundaries;
+
+  const order = options.priority;
+  let popper = data.offsets.popper;
+
+  const check = {
+    primary(placement) {
+      let value = popper[placement];
+      if (popper[placement] < boundaries[placement] && !options.escapeWithReference) {
+        value = Math.max(popper[placement], boundaries[placement]);
+      }
+      return { [placement]: value };
+    },
+    secondary(placement) {
+      const mainSide = placement === 'right' ? 'left' : 'top';
+      let value = popper[mainSide];
+      if (popper[placement] > boundaries[placement] && !options.escapeWithReference) {
+        value = Math.min(popper[mainSide], boundaries[placement] - (placement === 'right' ? popper.width : popper.height));
+      }
+      return { [mainSide]: value };
+    }
+  };
+
+  order.forEach(placement => {
+    const side = ['left', 'top'].indexOf(placement) !== -1 ? 'primary' : 'secondary';
+    popper = _extends({}, popper, check[side](placement));
+  });
+
+  data.offsets.popper = popper;
+
+  return data;
+}
+
+/**
+ * @function
+ * @memberof Modifiers
+ * @argument {Object} data - The data object generated by `update` method
+ * @argument {Object} options - Modifiers configuration and options
+ * @returns {Object} The data object, properly modified
+ */
+function shift(data) {
+  const placement = data.placement;
+  const basePlacement = placement.split('-')[0];
+  const shiftvariation = placement.split('-')[1];
+
+  // if shift shiftvariation is specified, run the modifier
+  if (shiftvariation) {
+    const { reference, popper } = data.offsets;
+    const isVertical = ['bottom', 'top'].indexOf(basePlacement) !== -1;
+    const side = isVertical ? 'left' : 'top';
+    const measurement = isVertical ? 'width' : 'height';
+
+    const shiftOffsets = {
+      start: { [side]: reference[side] },
+      end: {
+        [side]: reference[side] + reference[measurement] - popper[measurement]
+      }
+    };
+
+    data.offsets.popper = _extends({}, popper, shiftOffsets[shiftvariation]);
+  }
+
+  return data;
+}
+
+/**
+ * @function
+ * @memberof Modifiers
+ * @argument {Object} data - The data object generated by update method
+ * @argument {Object} options - Modifiers configuration and options
+ * @returns {Object} The data object, properly modified
+ */
+function hide(data) {
+  if (!isModifierRequired(data.instance.modifiers, 'hide', 'preventOverflow')) {
+    return data;
+  }
+
+  const refRect = data.offsets.reference;
+  const bound = find(data.instance.modifiers, modifier => modifier.name === 'preventOverflow').boundaries;
+
+  if (refRect.bottom < bound.top || refRect.left > bound.right || refRect.top > bound.bottom || refRect.right < bound.left) {
+    // Avoid unnecessary DOM access if visibility hasn't changed
+    if (data.hide === true) {
+      return data;
+    }
+
+    data.hide = true;
+    data.attributes['x-out-of-boundaries'] = '';
+  } else {
+    // Avoid unnecessary DOM access if visibility hasn't changed
+    if (data.hide === false) {
+      return data;
+    }
+
+    data.hide = false;
+    data.attributes['x-out-of-boundaries'] = false;
+  }
+
+  return data;
+}
+
+/**
+ * @function
+ * @memberof Modifiers
+ * @argument {Object} data - The data object generated by `update` method
+ * @argument {Object} options - Modifiers configuration and options
+ * @returns {Object} The data object, properly modified
+ */
+function inner(data) {
+  const placement = data.placement;
+  const basePlacement = placement.split('-')[0];
+  const { popper, reference } = data.offsets;
+  const isHoriz = ['left', 'right'].indexOf(basePlacement) !== -1;
+
+  const subtractLength = ['top', 'left'].indexOf(basePlacement) === -1;
+
+  popper[isHoriz ? 'left' : 'top'] = reference[basePlacement] - (subtractLength ? popper[isHoriz ? 'width' : 'height'] : 0);
+
+  data.placement = getOppositePlacement(placement);
+  data.offsets.popper = getClientRect(popper);
+
+  return data;
+}
+
+/**
+ * Modifier function, each modifier can have a function of this type assigned
+ * to its `fn` property.<br />
+ * These functions will be called on each update, this means that you must
+ * make sure they are performant enough to avoid performance bottlenecks.
+ *
+ * @function ModifierFn
+ * @argument {dataObject} data - The data object generated by `update` method
+ * @argument {Object} options - Modifiers configuration and options
+ * @returns {dataObject} The data object, properly modified
+ */
+
+/**
+ * Modifiers are plugins used to alter the behavior of your poppers.<br />
+ * Popper.js uses a set of 9 modifiers to provide all the basic functionalities
+ * needed by the library.
+ *
+ * Usually you don't want to override the `order`, `fn` and `onLoad` props.
+ * All the other properties are configurations that could be tweaked.
+ * @namespace modifiers
+ */
+var modifiers = {
+  /**
+   * Modifier used to shift the popper on the start or end of its reference
+   * element.<br />
+   * It will read the variation of the `placement` property.<br />
+   * It can be one either `-end` or `-start`.
+   * @memberof modifiers
+   * @inner
+   */
+  shift: {
+    /** @prop {number} order=100 - Index used to define the order of execution */
+    order: 100,
+    /** @prop {Boolean} enabled=true - Whether the modifier is enabled or not */
+    enabled: true,
+    /** @prop {ModifierFn} */
+    fn: shift
+  },
+
+  /**
+   * The `offset` modifier can shift your popper on both its axis.
+   *
+   * It accepts the following units:
+   * - `px` or unit-less, interpreted as pixels
+   * - `%` or `%r`, percentage relative to the length of the reference element
+   * - `%p`, percentage relative to the length of the popper element
+   * - `vw`, CSS viewport width unit
+   * - `vh`, CSS viewport height unit
+   *
+   * For length is intended the main axis relative to the placement of the popper.<br />
+   * This means that if the placement is `top` or `bottom`, the length will be the
+   * `width`. In case of `left` or `right`, it will be the `height`.
+   *
+   * You can provide a single value (as `Number` or `String`), or a pair of values
+   * as `String` divided by a comma or one (or more) white spaces.<br />
+   * The latter is a deprecated method because it leads to confusion and will be
+   * removed in v2.<br />
+   * Additionally, it accepts additions and subtractions between different units.
+   * Note that multiplications and divisions aren't supported.
+   *
+   * Valid examples are:
+   * ```
+   * 10
+   * '10%'
+   * '10, 10'
+   * '10%, 10'
+   * '10 + 10%'
+   * '10 - 5vh + 3%'
+   * '-10px + 5vh, 5px - 6%'
+   * ```
+   * > **NB**: If you desire to apply offsets to your poppers in a way that may make them overlap
+   * > with their reference element, unfortunately, you will have to disable the `flip` modifier.
+   * > You can read more on this at this [issue](https://github.com/FezVrasta/popper.js/issues/373).
+   *
+   * @memberof modifiers
+   * @inner
+   */
+  offset: {
+    /** @prop {number} order=200 - Index used to define the order of execution */
+    order: 200,
+    /** @prop {Boolean} enabled=true - Whether the modifier is enabled or not */
+    enabled: true,
+    /** @prop {ModifierFn} */
+    fn: offset,
+    /** @prop {Number|String} offset=0
+     * The offset value as described in the modifier description
+     */
+    offset: 0
+  },
+
+  /**
+   * Modifier used to prevent the popper from being positioned outside the boundary.
+   *
+   * A scenario exists where the reference itself is not within the boundaries.<br />
+   * We can say it has "escaped the boundaries" — or just "escaped".<br />
+   * In this case we need to decide whether the popper should either:
+   *
+   * - detach from the reference and remain "trapped" in the boundaries, or
+   * - if it should ignore the boundary and "escape with its reference"
+   *
+   * When `escapeWithReference` is set to`true` and reference is completely
+   * outside its boundaries, the popper will overflow (or completely leave)
+   * the boundaries in order to remain attached to the edge of the reference.
+   *
+   * @memberof modifiers
+   * @inner
+   */
+  preventOverflow: {
+    /** @prop {number} order=300 - Index used to define the order of execution */
+    order: 300,
+    /** @prop {Boolean} enabled=true - Whether the modifier is enabled or not */
+    enabled: true,
+    /** @prop {ModifierFn} */
+    fn: preventOverflow,
+    /**
+     * @prop {Array} [priority=['left','right','top','bottom']]
+     * Popper will try to prevent overflow following these priorities by default,
+     * then, it could overflow on the left and on top of the `boundariesElement`
+     */
+    priority: ['left', 'right', 'top', 'bottom'],
+    /**
+     * @prop {number} padding=5
+     * Amount of pixel used to define a minimum distance between the boundaries
+     * and the popper. This makes sure the popper always has a little padding
+     * between the edges of its container
+     */
+    padding: 5,
+    /**
+     * @prop {String|HTMLElement} boundariesElement='scrollParent'
+     * Boundaries used by the modifier. Can be `scrollParent`, `window`,
+     * `viewport` or any DOM element.
+     */
+    boundariesElement: 'scrollParent'
+  },
+
+  /**
+   * Modifier used to make sure the reference and its popper stay near each other
+   * without leaving any gap between the two. Especially useful when the arrow is
+   * enabled and you want to ensure that it points to its reference element.
+   * It cares only about the first axis. You can still have poppers with margin
+   * between the popper and its reference element.
+   * @memberof modifiers
+   * @inner
+   */
+  keepTogether: {
+    /** @prop {number} order=400 - Index used to define the order of execution */
+    order: 400,
+    /** @prop {Boolean} enabled=true - Whether the modifier is enabled or not */
+    enabled: true,
+    /** @prop {ModifierFn} */
+    fn: keepTogether
+  },
+
+  /**
+   * This modifier is used to move the `arrowElement` of the popper to make
+   * sure it is positioned between the reference element and its popper element.
+   * It will read the outer size of the `arrowElement` node to detect how many
+   * pixels of conjunction are needed.
+   *
+   * It has no effect if no `arrowElement` is provided.
+   * @memberof modifiers
+   * @inner
+   */
+  arrow: {
+    /** @prop {number} order=500 - Index used to define the order of execution */
+    order: 500,
+    /** @prop {Boolean} enabled=true - Whether the modifier is enabled or not */
+    enabled: true,
+    /** @prop {ModifierFn} */
+    fn: arrow,
+    /** @prop {String|HTMLElement} element='[x-arrow]' - Selector or node used as arrow */
+    element: '[x-arrow]'
+  },
+
+  /**
+   * Modifier used to flip the popper's placement when it starts to overlap its
+   * reference element.
+   *
+   * Requires the `preventOverflow` modifier before it in order to work.
+   *
+   * **NOTE:** this modifier will interrupt the current update cycle and will
+   * restart it if it detects the need to flip the placement.
+   * @memberof modifiers
+   * @inner
+   */
+  flip: {
+    /** @prop {number} order=600 - Index used to define the order of execution */
+    order: 600,
+    /** @prop {Boolean} enabled=true - Whether the modifier is enabled or not */
+    enabled: true,
+    /** @prop {ModifierFn} */
+    fn: flip,
+    /**
+     * @prop {String|Array} behavior='flip'
+     * The behavior used to change the popper's placement. It can be one of
+     * `flip`, `clockwise`, `counterclockwise` or an array with a list of valid
+     * placements (with optional variations)
+     */
+    behavior: 'flip',
+    /**
+     * @prop {number} padding=5
+     * The popper will flip if it hits the edges of the `boundariesElement`
+     */
+    padding: 5,
+    /**
+     * @prop {String|HTMLElement} boundariesElement='viewport'
+     * The element which will define the boundaries of the popper position.
+     * The popper will never be placed outside of the defined boundaries
+     * (except if `keepTogether` is enabled)
+     */
+    boundariesElement: 'viewport',
+    /**
+     * @prop {Boolean} flipVariations=false
+     * The popper will switch placement variation between `-start` and `-end` when
+     * the reference element overlaps its boundaries.
+     *
+     * The original placement should have a set variation.
+     */
+    flipVariations: false,
+    /**
+     * @prop {Boolean} flipVariationsByContent=false
+     * The popper will switch placement variation between `-start` and `-end` when
+     * the popper element overlaps its reference boundaries.
+     *
+     * The original placement should have a set variation.
+     */
+    flipVariationsByContent: false
+  },
+
+  /**
+   * Modifier used to make the popper flow toward the inner of the reference element.
+   * By default, when this modifier is disabled, the popper will be placed outside
+   * the reference element.
+   * @memberof modifiers
+   * @inner
+   */
+  inner: {
+    /** @prop {number} order=700 - Index used to define the order of execution */
+    order: 700,
+    /** @prop {Boolean} enabled=false - Whether the modifier is enabled or not */
+    enabled: false,
+    /** @prop {ModifierFn} */
+    fn: inner
+  },
+
+  /**
+   * Modifier used to hide the popper when its reference element is outside of the
+   * popper boundaries. It will set a `x-out-of-boundaries` attribute which can
+   * be used to hide with a CSS selector the popper when its reference is
+   * out of boundaries.
+   *
+   * Requires the `preventOverflow` modifier before it in order to work.
+   * @memberof modifiers
+   * @inner
+   */
+  hide: {
+    /** @prop {number} order=800 - Index used to define the order of execution */
+    order: 800,
+    /** @prop {Boolean} enabled=true - Whether the modifier is enabled or not */
+    enabled: true,
+    /** @prop {ModifierFn} */
+    fn: hide
+  },
+
+  /**
+   * Computes the style that will be applied to the popper element to gets
+   * properly positioned.
+   *
+   * Note that this modifier will not touch the DOM, it just prepares the styles
+   * so that `applyStyle` modifier can apply it. This separation is useful
+   * in case you need to replace `applyStyle` with a custom implementation.
+   *
+   * This modifier has `850` as `order` value to maintain backward compatibility
+   * with previous versions of Popper.js. Expect the modifiers ordering method
+   * to change in future major versions of the library.
+   *
+   * @memberof modifiers
+   * @inner
+   */
+  computeStyle: {
+    /** @prop {number} order=850 - Index used to define the order of execution */
+    order: 850,
+    /** @prop {Boolean} enabled=true - Whether the modifier is enabled or not */
+    enabled: true,
+    /** @prop {ModifierFn} */
+    fn: computeStyle,
+    /**
+     * @prop {Boolean} gpuAcceleration=true
+     * If true, it uses the CSS 3D transformation to position the popper.
+     * Otherwise, it will use the `top` and `left` properties
+     */
+    gpuAcceleration: true,
+    /**
+     * @prop {string} [x='bottom']
+     * Where to anchor the X axis (`bottom` or `top`). AKA X offset origin.
+     * Change this if your popper should grow in a direction different from `bottom`
+     */
+    x: 'bottom',
+    /**
+     * @prop {string} [x='left']
+     * Where to anchor the Y axis (`left` or `right`). AKA Y offset origin.
+     * Change this if your popper should grow in a direction different from `right`
+     */
+    y: 'right'
+  },
+
+  /**
+   * Applies the computed styles to the popper element.
+   *
+   * All the DOM manipulations are limited to this modifier. This is useful in case
+   * you want to integrate Popper.js inside a framework or view library and you
+   * want to delegate all the DOM manipulations to it.
+   *
+   * Note that if you disable this modifier, you must make sure the popper element
+   * has its position set to `absolute` before Popper.js can do its work!
+   *
+   * Just disable this modifier and define your own to achieve the desired effect.
+   *
+   * @memberof modifiers
+   * @inner
+   */
+  applyStyle: {
+    /** @prop {number} order=900 - Index used to define the order of execution */
+    order: 900,
+    /** @prop {Boolean} enabled=true - Whether the modifier is enabled or not */
+    enabled: true,
+    /** @prop {ModifierFn} */
+    fn: applyStyle,
+    /** @prop {Function} */
+    onLoad: applyStyleOnLoad,
+    /**
+     * @deprecated since version 1.10.0, the property moved to `computeStyle` modifier
+     * @prop {Boolean} gpuAcceleration=true
+     * If true, it uses the CSS 3D transformation to position the popper.
+     * Otherwise, it will use the `top` and `left` properties
+     */
+    gpuAcceleration: undefined
+  }
+};
+
+/**
+ * The `dataObject` is an object containing all the information used by Popper.js.
+ * This object is passed to modifiers and to the `onCreate` and `onUpdate` callbacks.
+ * @name dataObject
+ * @property {Object} data.instance The Popper.js instance
+ * @property {String} data.placement Placement applied to popper
+ * @property {String} data.originalPlacement Placement originally defined on init
+ * @property {Boolean} data.flipped True if popper has been flipped by flip modifier
+ * @property {Boolean} data.hide True if the reference element is out of boundaries, useful to know when to hide the popper
+ * @property {HTMLElement} data.arrowElement Node used as arrow by arrow modifier
+ * @property {Object} data.styles Any CSS property defined here will be applied to the popper. It expects the JavaScript nomenclature (eg. `marginBottom`)
+ * @property {Object} data.arrowStyles Any CSS property defined here will be applied to the popper arrow. It expects the JavaScript nomenclature (eg. `marginBottom`)
+ * @property {Object} data.boundaries Offsets of the popper boundaries
+ * @property {Object} data.offsets The measurements of popper, reference and arrow elements
+ * @property {Object} data.offsets.popper `top`, `left`, `width`, `height` values
+ * @property {Object} data.offsets.reference `top`, `left`, `width`, `height` values
+ * @property {Object} data.offsets.arrow] `top` and `left` offsets, only one of them will be different from 0
+ */
+
+/**
+ * Default options provided to Popper.js constructor.<br />
+ * These can be overridden using the `options` argument of Popper.js.<br />
+ * To override an option, simply pass an object with the same
+ * structure of the `options` object, as the 3rd argument. For example:
+ * ```
+ * new Popper(ref, pop, {
+ *   modifiers: {
+ *     preventOverflow: { enabled: false }
+ *   }
+ * })
+ * ```
+ * @type {Object}
+ * @static
+ * @memberof Popper
+ */
+var Defaults = {
+  /**
+   * Popper's placement.
+   * @prop {Popper.placements} placement='bottom'
+   */
+  placement: 'bottom',
+
+  /**
+   * Set this to true if you want popper to position it self in 'fixed' mode
+   * @prop {Boolean} positionFixed=false
+   */
+  positionFixed: false,
+
+  /**
+   * Whether events (resize, scroll) are initially enabled.
+   * @prop {Boolean} eventsEnabled=true
+   */
+  eventsEnabled: true,
+
+  /**
+   * Set to true if you want to automatically remove the popper when
+   * you call the `destroy` method.
+   * @prop {Boolean} removeOnDestroy=false
+   */
+  removeOnDestroy: false,
+
+  /**
+   * Callback called when the popper is created.<br />
+   * By default, it is set to no-op.<br />
+   * Access Popper.js instance with `data.instance`.
+   * @prop {onCreate}
+   */
+  onCreate: () => {},
+
+  /**
+   * Callback called when the popper is updated. This callback is not called
+   * on the initialization/creation of the popper, but only on subsequent
+   * updates.<br />
+   * By default, it is set to no-op.<br />
+   * Access Popper.js instance with `data.instance`.
+   * @prop {onUpdate}
+   */
+  onUpdate: () => {},
+
+  /**
+   * List of modifiers used to modify the offsets before they are applied to the popper.
+   * They provide most of the functionalities of Popper.js.
+   * @prop {modifiers}
+   */
+  modifiers
+};
+
+/**
+ * @callback onCreate
+ * @param {dataObject} data
+ */
+
+/**
+ * @callback onUpdate
+ * @param {dataObject} data
+ */
+
+// Utils
+// Methods
+class Popper {
+  /**
+   * Creates a new Popper.js instance.
+   * @class Popper
+   * @param {Element|referenceObject} reference - The reference element used to position the popper
+   * @param {Element} popper - The HTML / XML element used as the popper
+   * @param {Object} options - Your custom options to override the ones defined in [Defaults](#defaults)
+   * @return {Object} instance - The generated Popper.js instance
+   */
+  constructor(reference, popper, options = {}) {
+    this.scheduleUpdate = () => requestAnimationFrame(this.update);
+
+    // make update() debounced, so that it only runs at most once-per-tick
+    this.update = debounce(this.update.bind(this));
+
+    // with {} we create a new object with the options inside it
+    this.options = _extends({}, Popper.Defaults, options);
+
+    // init state
+    this.state = {
+      isDestroyed: false,
+      isCreated: false,
+      scrollParents: []
+    };
+
+    // get reference and popper elements (allow jQuery wrappers)
+    this.reference = reference && reference.jquery ? reference[0] : reference;
+    this.popper = popper && popper.jquery ? popper[0] : popper;
+
+    // Deep merge modifiers options
+    this.options.modifiers = {};
+    Object.keys(_extends({}, Popper.Defaults.modifiers, options.modifiers)).forEach(name => {
+      this.options.modifiers[name] = _extends({}, Popper.Defaults.modifiers[name] || {}, options.modifiers ? options.modifiers[name] : {});
+    });
+
+    // Refactoring modifiers' list (Object => Array)
+    this.modifiers = Object.keys(this.options.modifiers).map(name => _extends({
+      name
+    }, this.options.modifiers[name]))
+    // sort the modifiers by order
+    .sort((a, b) => a.order - b.order);
+
+    // modifiers have the ability to execute arbitrary code when Popper.js get inited
+    // such code is executed in the same order of its modifier
+    // they could add new properties to their options configuration
+    // BE AWARE: don't add options to `options.modifiers.name` but to `modifierOptions`!
+    this.modifiers.forEach(modifierOptions => {
+      if (modifierOptions.enabled && isFunction(modifierOptions.onLoad)) {
+        modifierOptions.onLoad(this.reference, this.popper, this.options, modifierOptions, this.state);
+      }
+    });
+
+    // fire the first update to position the popper in the right place
+    this.update();
+
+    const eventsEnabled = this.options.eventsEnabled;
+    if (eventsEnabled) {
+      // setup event listeners, they will take care of update the position in specific situations
+      this.enableEventListeners();
+    }
+
+    this.state.eventsEnabled = eventsEnabled;
+  }
+
+  // We can't use class properties because they don't get listed in the
+  // class prototype and break stuff like Sinon stubs
+  update() {
+    return update.call(this);
+  }
+  destroy() {
+    return destroy.call(this);
+  }
+  enableEventListeners() {
+    return enableEventListeners.call(this);
+  }
+  disableEventListeners() {
+    return disableEventListeners.call(this);
+  }
+
+  /**
+   * Schedules an update. It will run on the next UI update available.
+   * @method scheduleUpdate
+   * @memberof Popper
+   */
+
+
+  /**
+   * Collection of utilities useful when writing custom modifiers.
+   * Starting from version 1.7, this method is available only if you
+   * include `popper-utils.js` before `popper.js`.
+   *
+   * **DEPRECATION**: This way to access PopperUtils is deprecated
+   * and will be removed in v2! Use the PopperUtils module directly instead.
+   * Due to the high instability of the methods contained in Utils, we can't
+   * guarantee them to follow semver. Use them at your own risk!
+   * @static
+   * @private
+   * @type {Object}
+   * @deprecated since version 1.8
+   * @member Utils
+   * @memberof Popper
+   */
+}
+
+/**
+ * The `referenceObject` is an object that provides an interface compatible with Popper.js
+ * and lets you use it as replacement of a real DOM node.<br />
+ * You can use this method to position a popper relatively to a set of coordinates
+ * in case you don't have a DOM node to use as reference.
+ *
+ * ```
+ * new Popper(referenceObject, popperNode);
+ * ```
+ *
+ * NB: This feature isn't supported in Internet Explorer 10.
+ * @name referenceObject
+ * @property {Function} data.getBoundingClientRect
+ * A function that returns a set of coordinates compatible with the native `getBoundingClientRect` method.
+ * @property {number} data.clientWidth
+ * An ES6 getter that will return the width of the virtual reference element.
+ * @property {number} data.clientHeight
+ * An ES6 getter that will return the height of the virtual reference element.
+ */
+
+Popper.Utils = (typeof window !== 'undefined' ? window : global).PopperUtils;
+Popper.placements = placements;
+Popper.Defaults = Defaults;
+
+export default Popper;
+//# sourceMappingURL=popper.js.map