Drop Legacy Edge support.

.browserslistrc

@@ -5,7 +5,7 @@ last 1 major version
 not dead
 Chrome >= 60
 Firefox >= 60
-Edge >= 16
+not Edge < 79
 iOS >= 10
 Safari >= 10
 Android >= 6

js/src/dom/event-handler.js

@@ -6,7 +6,6 @@
  */
 
 import { getjQuery } from '../util/index'
-import { defaultPreventedPreservedOnDispatch } from './polyfill'
 
 /**
  * ------------------------------------------------------------------------
@@ -314,12 +313,6 @@ const EventHandler = {
 
     if (defaultPrevented) {
       evt.preventDefault()
-
-      if (!defaultPreventedPreservedOnDispatch) {
-        Object.defineProperty(evt, 'defaultPrevented', {
-          get: () => true
-        })
-      }
     }
 
     if (nativeDispatch) {

js/src/dom/polyfill.js

@@ -12,20 +12,6 @@ import { getUID } from '../util/index'
 let find = Element.prototype.querySelectorAll
 let findOne = Element.prototype.querySelector
 
-// MSEdge resets defaultPrevented flag upon dispatchEvent call if at least one listener is attached
-const defaultPreventedPreservedOnDispatch = (() => {
-  const e = new CustomEvent('Bootstrap', {
-    cancelable: true
-  })
-
-  const element = document.createElement('div')
-  element.addEventListener('Bootstrap', () => null)
-
-  e.preventDefault()
-  element.dispatchEvent(e)
-  return e.defaultPrevented
-})()
-
 const scopeSelectorRegex = /:scope\b/
 const supportScopeQuery = (() => {
   const element = document.createElement('div')
@@ -81,6 +67,5 @@ if (!supportScopeQuery) {
 
 export {
   find,
-  findOne,
-  defaultPreventedPreservedOnDispatch
+  findOne
 }

js/tests/browsers.js

@@ -23,13 +23,6 @@ const browsers = {
     browser: 'Firefox',
     browser_version: 'latest'
   },
-  edgeWin10: {
-    base: 'BrowserStack',
-    os: 'Windows',
-    os_version: '10',
-    browser: 'Edge',
-    browser_version: '16'
-  },
   chromeWin10: {
     base: 'BrowserStack',
     os: 'Windows',

js/tests/visual/tooltip.html

@@ -12,8 +12,6 @@
         height: 50px;
         border: 1px solid;
         margin-left: 50px;
-        -webkit-transform: rotate(270deg);
-        -ms-transform: rotate(270deg);
         transform: rotate(270deg);
         margin-top: 100px;
       }

scss/_reboot.scss

@@ -295,8 +295,6 @@ samp {
 // 1. Remove browser default top margin
 // 2. Reset browser default of `1em` to use `rem`s
 // 3. Don't allow content to break outside
-// 4. Disable auto-hiding scrollbar in legacy Edge to avoid overlap,
-//    making it impossible to interact with the content
 
 pre {
   display: block;
@@ -305,7 +303,6 @@ pre {
   overflow: auto; // 3
   @include font-size($code-font-size);
   color: $pre-color;
-  -ms-overflow-style: scrollbar; // 4
 
   // Account for some code outputs that place code tags in pre tags
   code {
@@ -434,13 +431,6 @@ textarea {
   line-height: inherit;
 }
 
-// Show the overflow in Edge
-
-button,
-input {
-  overflow: visible;
-}
-
 // Remove the inheritance of text transform in Firefox
 
 button,
@@ -516,8 +506,7 @@ fieldset {
 
 // 1. By using `float: left`, the legend will behave like a block element.
 //    This way the border of a fieldset wraps around the legend if present.
-// 2. Correct the text wrapping in Edge.
-// 3. Fix wrapping bug.
+// 2. Fix wrapping bug.
 //    See https://github.com/twbs/bootstrap/issues/29712
 
 legend {
@@ -528,10 +517,9 @@ legend {
   @include font-size($legend-font-size);
   font-weight: $legend-font-weight;
   line-height: inherit;
-  white-space: normal; // 2
 
   + * {
-    clear: left; // 3
+    clear: left; // 2
   }
 }
 

scss/forms/_form-range.scss

@@ -18,7 +18,6 @@
     // No box-shadow() mixin for focus accessibility.
     &::-webkit-slider-thumb { box-shadow: $form-range-thumb-focus-box-shadow; }
     &::-moz-range-thumb     { box-shadow: $form-range-thumb-focus-box-shadow; }
-    &::-ms-thumb            { box-shadow: $form-range-thumb-focus-box-shadow; }
   }
 
   &::-moz-focus-outer {
@@ -78,46 +77,6 @@
     @include box-shadow($form-range-track-box-shadow);
   }
 
-  &::-ms-thumb {
-    width: $form-range-thumb-width;
-    height: $form-range-thumb-height;
-    margin-top: 0; // Edge specific
-    margin-right: $form-range-thumb-focus-box-shadow-width; // Workaround that overflowed box-shadow is hidden.
-    margin-left: $form-range-thumb-focus-box-shadow-width;  // Workaround that overflowed box-shadow is hidden.
-    @include gradient-bg($form-range-thumb-bg);
-    border: $form-range-thumb-border;
-    @include border-radius($form-range-thumb-border-radius);
-    @include box-shadow($form-range-thumb-box-shadow);
-    @include transition($form-range-thumb-transition);
-    appearance: none;
-
-    &:active {
-      @include gradient-bg($form-range-thumb-active-bg);
-    }
-  }
-
-  &::-ms-track {
-    width: $form-range-track-width;
-    height: $form-range-track-height;
-    color: transparent;
-    cursor: $form-range-track-cursor;
-    background-color: transparent;
-    border-color: transparent;
-    border-width: $form-range-thumb-height / 2;
-    @include box-shadow($form-range-track-box-shadow);
-  }
-
-  &::-ms-fill-lower {
-    background-color: $form-range-track-bg;
-    @include border-radius($form-range-track-border-radius);
-  }
-
-  &::-ms-fill-upper {
-    margin-right: 15px; // arbitrary?
-    background-color: $form-range-track-bg;
-    @include border-radius($form-range-track-border-radius);
-  }
-
   &:disabled {
     pointer-events: none;
 
@@ -128,9 +87,5 @@
     &::-moz-range-thumb {
       background-color: $form-range-thumb-disabled-bg;
     }
-
-    &::-ms-thumb {
-      background-color: $form-range-thumb-disabled-bg;
-    }
   }
 }

scss/forms/_form-select.scss

@@ -33,16 +33,6 @@
       // Avoid using mixin so we can pass custom focus shadow properly
       box-shadow: $form-select-focus-box-shadow;
     }
-
-    &::-ms-value {
-      // For visual consistency with other platforms/browsers,
-      // suppress the default white text on blue background highlight given to
-      // the selected option text when the (still closed) <select> receives focus
-      // in Edge.
-      // See https://github.com/twbs/bootstrap/issues/19398.
-      color: $input-color;
-      background-color: $input-bg;
-    }
   }
 
   &[multiple],

site/assets/scss/_component-examples.scss

@@ -273,7 +273,6 @@
   padding: 1rem;
   margin-bottom: 1rem;
   background-color: $gray-100;
-  -ms-overflow-style: -ms-autohiding-scrollbar;
 
   @include media-breakpoint-up(sm) {
     padding: 1rem 1.5rem;

site/content/docs/5.0/examples/floating-labels/floating-labels.css

@@ -51,10 +51,6 @@ body {
   color: transparent;
 }
 
-.form-label-group input::-ms-input-placeholder {
-  color: transparent;
-}
-
 .form-label-group input::placeholder {
   color: transparent;
 }
@@ -82,20 +78,3 @@ body {
   font-size: 12px;
   color: #777;
 }
-
-/* Fallback for Edge
--------------------------------------------------- */
-@supports (-ms-ime-align: auto) {
-  .form-label-group {
-    display: flex;
-    flex-direction: column-reverse;
-  }
-
-  .form-label-group label {
-    position: static;
-  }
-
-  .form-label-group input::-ms-input-placeholder {
-    color: #777;
-  }
-}

site/content/docs/5.0/migration.md

@@ -9,6 +9,10 @@ toc: true
 
 ## v5.0.0-alpha3
 
+### Browser support
+
+- Dropped support for Microsoft Legacy Edge. See [here](#browser-support-1) for the previous browser support changes.
+
 ### Colors
 
 - The color system which worked with `color-level()` and `$theme-color-interval` was removed in favor of a new color system.

site/layouts/_default/examples.html

@@ -23,7 +23,6 @@
         text-anchor: middle;
         -webkit-user-select: none;
         -moz-user-select: none;
-        -ms-user-select: none;
         user-select: none;
       }