Update to 4.6.0v4.6.0

1. rake 'update[v4.6.0]'
2. Bump version in lib/boostrap/version.rb and README.md

29 files changed, 122 insertions, 70 deletions

diff --git a/assets/stylesheets/_bootstrap-grid.scss b/assets/stylesheets/_bootstrap-grid.scss
index 668ad18..94b2af1 100644
--- a/assets/stylesheets/_bootstrap-grid.scss
+++ b/assets/stylesheets/_bootstrap-grid.scss
@@ -1,7 +1,7 @@
 /*!
- * Bootstrap Grid v4.5.2 (https://getbootstrap.com/)
- * Copyright 2011-2020 The Bootstrap Authors
- * Copyright 2011-2020 Twitter, Inc.
+ * Bootstrap Grid v4.6.0 (https://getbootstrap.com/)
+ * Copyright 2011-2021 The Bootstrap Authors
+ * Copyright 2011-2021 Twitter, Inc.
  * Licensed under MIT (https://github.com/twbs/bootstrap/blob/main/LICENSE)
  */
 
@@ -19,6 +19,7 @@ html {
 @import "bootstrap/functions";
 @import "bootstrap/variables";
 
+@import "bootstrap/mixins/deprecate";
 @import "bootstrap/mixins/breakpoints";
 @import "bootstrap/mixins/grid-framework";
 @import "bootstrap/mixins/grid";
diff --git a/assets/stylesheets/_bootstrap-reboot.scss b/assets/stylesheets/_bootstrap-reboot.scss
index d55c7ce..86987bc 100644
--- a/assets/stylesheets/_bootstrap-reboot.scss
+++ b/assets/stylesheets/_bootstrap-reboot.scss
@@ -1,7 +1,7 @@
 /*!
- * Bootstrap Reboot v4.5.2 (https://getbootstrap.com/)
- * Copyright 2011-2020 The Bootstrap Authors
- * Copyright 2011-2020 Twitter, Inc.
+ * Bootstrap Reboot v4.6.0 (https://getbootstrap.com/)
+ * Copyright 2011-2021 The Bootstrap Authors
+ * Copyright 2011-2021 Twitter, Inc.
  * Licensed under MIT (https://github.com/twbs/bootstrap/blob/main/LICENSE)
  * Forked from Normalize.css, licensed MIT (https://github.com/necolas/normalize.css/blob/master/LICENSE.md)
  */
diff --git a/assets/stylesheets/_bootstrap.scss b/assets/stylesheets/_bootstrap.scss
index b8a3178..cfd3b7b 100644
--- a/assets/stylesheets/_bootstrap.scss
+++ b/assets/stylesheets/_bootstrap.scss
@@ -1,7 +1,7 @@
 /*!
- * Bootstrap v4.5.2 (https://getbootstrap.com/)
- * Copyright 2011-2020 The Bootstrap Authors
- * Copyright 2011-2020 Twitter, Inc.
+ * Bootstrap v4.6.0 (https://getbootstrap.com/)
+ * Copyright 2011-2021 The Bootstrap Authors
+ * Copyright 2011-2021 Twitter, Inc.
  * Licensed under MIT (https://github.com/twbs/bootstrap/blob/main/LICENSE)
  */
 
diff --git a/assets/stylesheets/bootstrap/_alert.scss b/assets/stylesheets/bootstrap/_alert.scss
index da2a98a..4aa1fc2 100644
--- a/assets/stylesheets/bootstrap/_alert.scss
+++ b/assets/stylesheets/bootstrap/_alert.scss
@@ -34,6 +34,7 @@
     position: absolute;
     top: 0;
     right: 0;
+    z-index: 2;
     padding: $alert-padding-y $alert-padding-x;
     color: inherit;
   }
diff --git a/assets/stylesheets/bootstrap/_breadcrumb.scss b/assets/stylesheets/bootstrap/_breadcrumb.scss
index a0cf7e2..9c204c7 100644
--- a/assets/stylesheets/bootstrap/_breadcrumb.scss
+++ b/assets/stylesheets/bootstrap/_breadcrumb.scss
@@ -10,14 +10,12 @@
 }
 
 .breadcrumb-item {
-  display: flex;
-
   // The separator between breadcrumbs (by default, a forward-slash: "/")
   + .breadcrumb-item {
     padding-left: $breadcrumb-item-padding;
 
     &::before {
-      display: inline-block; // Suppress underlining of the separator in modern browsers
+      float: left; // Suppress inline spacings and underlining of the separator
       padding-right: $breadcrumb-item-padding;
       color: $breadcrumb-divider-color;
       content: escape-svg($breadcrumb-divider);
diff --git a/assets/stylesheets/bootstrap/_card.scss b/assets/stylesheets/bootstrap/_card.scss
index 7c35f7e..faaa75e 100644
--- a/assets/stylesheets/bootstrap/_card.scss
+++ b/assets/stylesheets/bootstrap/_card.scss
@@ -206,12 +206,12 @@
 
           .card-img-top,
           .card-header {
-            // stylelint-disable-next-line property-blacklist
+            // stylelint-disable-next-line property-disallowed-list
             border-top-right-radius: 0;
           }
           .card-img-bottom,
           .card-footer {
-            // stylelint-disable-next-line property-blacklist
+            // stylelint-disable-next-line property-disallowed-list
             border-bottom-right-radius: 0;
           }
         }
@@ -221,12 +221,12 @@
 
           .card-img-top,
           .card-header {
-            // stylelint-disable-next-line property-blacklist
+            // stylelint-disable-next-line property-disallowed-list
             border-top-left-radius: 0;
           }
           .card-img-bottom,
           .card-footer {
-            // stylelint-disable-next-line property-blacklist
+            // stylelint-disable-next-line property-disallowed-list
             border-bottom-left-radius: 0;
           }
         }
diff --git a/assets/stylesheets/bootstrap/_carousel.scss b/assets/stylesheets/bootstrap/_carousel.scss
index fb5e9f8..db30bed 100644
--- a/assets/stylesheets/bootstrap/_carousel.scss
+++ b/assets/stylesheets/bootstrap/_carousel.scss
@@ -127,7 +127,7 @@
   display: inline-block;
   width: $carousel-control-icon-width;
   height: $carousel-control-icon-width;
-  background: no-repeat 50% / 100% 100%;
+  background: 50% / 100% 100% no-repeat;
 }
 .carousel-control-prev-icon {
   background-image: escape-svg($carousel-control-prev-icon-bg);
diff --git a/assets/stylesheets/bootstrap/_custom-forms.scss b/assets/stylesheets/bootstrap/_custom-forms.scss
index 9aeeeda..06725ff 100644
--- a/assets/stylesheets/bootstrap/_custom-forms.scss
+++ b/assets/stylesheets/bootstrap/_custom-forms.scss
@@ -13,6 +13,7 @@
   display: block;
   min-height: $font-size-base * $line-height-base;
   padding-left: $custom-control-gutter + $custom-control-indicator-size;
+  color-adjust: exact; // Keep themed appearance for print
 }
 
 .custom-control-inline {
@@ -38,7 +39,7 @@
   &:focus ~ .custom-control-label::before {
     // the mixin is not used here to make sure there is feedback
     @if $enable-shadows {
-      box-shadow: $input-box-shadow, $input-focus-box-shadow;
+      box-shadow: $input-box-shadow, $custom-control-indicator-focus-box-shadow;
     } @else {
       box-shadow: $custom-control-indicator-focus-box-shadow;
     }
@@ -103,7 +104,7 @@
     width: $custom-control-indicator-size;
     height: $custom-control-indicator-size;
     content: "";
-    background: no-repeat 50% / #{$custom-control-indicator-bg-size};
+    background: 50% / #{$custom-control-indicator-bg-size} no-repeat;
   }
 }
 
@@ -150,7 +151,7 @@
 
 .custom-radio {
   .custom-control-label::before {
-    // stylelint-disable-next-line property-blacklist
+    // stylelint-disable-next-line property-disallowed-list
     border-radius: $custom-radio-indicator-border-radius;
   }
 
@@ -180,7 +181,7 @@
       left: -($custom-switch-width + $custom-control-gutter);
       width: $custom-switch-width;
       pointer-events: all;
-      // stylelint-disable-next-line property-blacklist
+      // stylelint-disable-next-line property-disallowed-list
       border-radius: $custom-switch-indicator-border-radius;
     }
 
@@ -190,7 +191,7 @@
       width: $custom-switch-indicator-size;
       height: $custom-switch-indicator-size;
       background-color: $custom-control-indicator-border-color;
-      // stylelint-disable-next-line property-blacklist
+      // stylelint-disable-next-line property-disallowed-list
       border-radius: $custom-switch-indicator-border-radius;
       @include transition(transform .15s ease-in-out, $custom-forms-transition);
     }
@@ -314,6 +315,7 @@
   width: 100%;
   height: $custom-file-height;
   margin: 0;
+  overflow: hidden;
   opacity: 0;
 
   &:focus ~ .custom-file-label {
@@ -346,6 +348,7 @@
   z-index: 1;
   height: $custom-file-height;
   padding: $custom-file-padding-y $custom-file-padding-x;
+  overflow: hidden;
   font-family: $custom-file-font-family;
   font-weight: $custom-file-font-weight;
   line-height: $custom-file-line-height;
@@ -387,7 +390,7 @@
   appearance: none;
 
   &:focus {
-    outline: none;
+    outline: 0;
 
     // Pseudo-elements must be split across multiple rulesets to have an effect.
     // No box-shadow() mixin for focus accessibility.
diff --git a/assets/stylesheets/bootstrap/_dropdown.scss b/assets/stylesheets/bootstrap/_dropdown.scss
index 2ab7536..f39de11 100644
--- a/assets/stylesheets/bootstrap/_dropdown.scss
+++ b/assets/stylesheets/bootstrap/_dropdown.scss
@@ -22,7 +22,7 @@
   display: none; // none by default, but block on "open" of the menu
   float: left;
   min-width: $dropdown-min-width;
-  padding: $dropdown-padding-y 0;
+  padding: $dropdown-padding-y $dropdown-padding-x;
   margin: $dropdown-spacer 0 0; // override default ul
   @include font-size($dropdown-font-size);
   color: $dropdown-color;
@@ -100,7 +100,7 @@
   }
 }
 
-// When enabled Popper.js, reset basic dropdown position
+// When Popper is enabled, reset the basic dropdown position
 // stylelint-disable-next-line no-duplicate-selectors
 .dropdown-menu {
   &[x-placement^="top"],
diff --git a/assets/stylesheets/bootstrap/_functions.scss b/assets/stylesheets/bootstrap/_functions.scss
index eb2471d..9c06603 100644
--- a/assets/stylesheets/bootstrap/_functions.scss
+++ b/assets/stylesheets/bootstrap/_functions.scss
@@ -51,6 +51,9 @@
 }
 
 // See https://codepen.io/kevinweber/pen/dXWoRw
+//
+// Requires the use of quotes around data URIs.
+
 @function escape-svg($string) {
   @if str-index($string, "data:image/svg+xml") {
     @each $char, $encoded in $escaped-characters {
diff --git a/assets/stylesheets/bootstrap/_input-group.scss b/assets/stylesheets/bootstrap/_input-group.scss
index cad8ea3..d72ebea 100644
--- a/assets/stylesheets/bootstrap/_input-group.scss
+++ b/assets/stylesheets/bootstrap/_input-group.scss
@@ -42,7 +42,6 @@
 
   > .form-control,
   > .custom-select {
-    &:not(:last-child) { @include border-right-radius(0); }
     &:not(:first-child) { @include border-left-radius(0); }
   }
 
@@ -53,9 +52,24 @@
     align-items: center;
 
     &:not(:last-child) .custom-file-label,
-    &:not(:last-child) .custom-file-label::after { @include border-right-radius(0); }
     &:not(:first-child) .custom-file-label { @include border-left-radius(0); }
   }
+
+  &:not(.has-validation) {
+    > .form-control:not(:last-child),
+    > .custom-select:not(:last-child),
+    > .custom-file:not(:last-child) .custom-file-label::after {
+      @include border-right-radius(0);
+    }
+  }
+
+  &.has-validation {
+    > .form-control:nth-last-child(n + 3),
+    > .custom-select:nth-last-child(n + 3),
+    > .custom-file:nth-last-child(n + 3) .custom-file-label::after {
+      @include border-right-radius(0);
+    }
+  }
 }
 
 
@@ -175,8 +189,10 @@
 
 .input-group > .input-group-prepend > .btn,
 .input-group > .input-group-prepend > .input-group-text,
-.input-group > .input-group-append:not(:last-child) > .btn,
-.input-group > .input-group-append:not(:last-child) > .input-group-text,
+.input-group:not(.has-validation) > .input-group-append:not(:last-child) > .btn,
+.input-group:not(.has-validation) > .input-group-append:not(:last-child) > .input-group-text,
+.input-group.has-validation > .input-group-append:nth-last-child(n + 3) > .btn,
+.input-group.has-validation > .input-group-append:nth-last-child(n + 3) > .input-group-text,
 .input-group > .input-group-append:last-child > .btn:not(:last-child):not(.dropdown-toggle),
 .input-group > .input-group-append:last-child > .input-group-text:not(:last-child) {
   @include border-right-radius(0);
diff --git a/assets/stylesheets/bootstrap/_list-group.scss b/assets/stylesheets/bootstrap/_list-group.scss
index 37c307e..ec25ba8 100644
--- a/assets/stylesheets/bootstrap/_list-group.scss
+++ b/assets/stylesheets/bootstrap/_list-group.scss
@@ -111,7 +111,7 @@
           margin-top: 0;
         }
 
-        & + .list-group-item {
+        + .list-group-item {
           border-top-width: $list-group-border-width;
           border-left-width: 0;
 
diff --git a/assets/stylesheets/bootstrap/_nav.scss b/assets/stylesheets/bootstrap/_nav.scss
index d866c98..fad684e 100644
--- a/assets/stylesheets/bootstrap/_nav.scss
+++ b/assets/stylesheets/bootstrap/_nav.scss
@@ -35,11 +35,8 @@
 .nav-tabs {
   border-bottom: $nav-tabs-border-width solid $nav-tabs-border-color;
 
-  .nav-item {
-    margin-bottom: -$nav-tabs-border-width;
-  }
-
   .nav-link {
+    margin-bottom: -$nav-tabs-border-width;
     border: $nav-tabs-border-width solid transparent;
     @include border-top-radius($nav-tabs-border-radius);
 
diff --git a/assets/stylesheets/bootstrap/_navbar.scss b/assets/stylesheets/bootstrap/_navbar.scss
index 5f10a62..cf5b667 100644
--- a/assets/stylesheets/bootstrap/_navbar.scss
+++ b/assets/stylesheets/bootstrap/_navbar.scss
@@ -136,8 +136,12 @@
   height: 1.5em;
   vertical-align: middle;
   content: "";
-  background: no-repeat center center;
-  background-size: 100% 100%;
+  background: 50% / 100% 100% no-repeat;
+}
+
+.navbar-nav-scroll {
+  max-height: $navbar-nav-scroll-max-height;
+  overflow-y: auto;
 }
 
 // Generate series of `.navbar-expand-*` responsive classes for configuring
@@ -199,6 +203,10 @@
           }
         }
 
+        .navbar-nav-scroll {
+          overflow: visible;
+        }
+
         .navbar-collapse {
           display: flex !important; // stylelint-disable-line declaration-no-important
 
diff --git a/assets/stylesheets/bootstrap/_pagination.scss b/assets/stylesheets/bootstrap/_pagination.scss
index d7d553c..9313cc5 100644
--- a/assets/stylesheets/bootstrap/_pagination.scss
+++ b/assets/stylesheets/bootstrap/_pagination.scss
@@ -66,9 +66,9 @@
 //
 
 .pagination-lg {
-  @include pagination-size($pagination-padding-y-lg, $pagination-padding-x-lg, $font-size-lg, $line-height-lg, $border-radius-lg);
+  @include pagination-size($pagination-padding-y-lg, $pagination-padding-x-lg, $font-size-lg, $line-height-lg, $pagination-border-radius-lg);
 }
 
 .pagination-sm {
-  @include pagination-size($pagination-padding-y-sm, $pagination-padding-x-sm, $font-size-sm, $line-height-sm, $border-radius-sm);
+  @include pagination-size($pagination-padding-y-sm, $pagination-padding-x-sm, $font-size-sm, $line-height-sm, $pagination-border-radius-sm);
 }
diff --git a/assets/stylesheets/bootstrap/_progress.scss b/assets/stylesheets/bootstrap/_progress.scss
index 1a03704..e206474 100644
--- a/assets/stylesheets/bootstrap/_progress.scss
+++ b/assets/stylesheets/bootstrap/_progress.scss
@@ -36,7 +36,7 @@
 
 @if $enable-transitions {
   .progress-bar-animated {
-    animation: progress-bar-stripes $progress-bar-animation-timing;
+    animation: $progress-bar-animation-timing progress-bar-stripes;
 
     @if $enable-prefers-reduced-motion-media-query {
       @media (prefers-reduced-motion: reduce) {
diff --git a/assets/stylesheets/bootstrap/_reboot.scss b/assets/stylesheets/bootstrap/_reboot.scss
index 4444ff0..cd93bfe 100644
--- a/assets/stylesheets/bootstrap/_reboot.scss
+++ b/assets/stylesheets/bootstrap/_reboot.scss
@@ -1,4 +1,4 @@
-// stylelint-disable at-rule-no-vendor-prefix, declaration-no-important, selector-no-qualifying-type, property-no-vendor-prefix
+// stylelint-disable declaration-no-important, selector-no-qualifying-type, property-no-vendor-prefix
 
 // Reboot
 //
@@ -278,10 +278,14 @@ caption {
   caption-side: bottom;
 }
 
+// 1. Removes font-weight bold by inheriting
+// 2. Matches default `<td>` alignment by inheriting `text-align`.
+// 3. Fix alignment for Safari
+
 th {
-  // Matches default `<td>` alignment by inheriting from the `<body>`, or the
-  // closest parent with a set `text-align`.
-  text-align: inherit;
+  font-weight: $table-th-font-weight; // 1
+  text-align: inherit; // 2
+  text-align: -webkit-match-parent; // 3
 }
 
 
@@ -299,17 +303,17 @@ label {
 //
 // Details at https://github.com/twbs/bootstrap/issues/24093
 button {
-  // stylelint-disable-next-line property-blacklist
+  // stylelint-disable-next-line property-disallowed-list
   border-radius: 0;
 }
 
-// Work around a Firefox/IE bug where the transparent `button` background
-// results in a loss of the default `button` focus styles.
-//
-// Credit: https://github.com/suitcss/base/
-button:focus {
-  outline: 1px dotted;
-  outline: 5px auto -webkit-focus-ring-color;
+// Explicitly remove focus outline in Chromium when it shouldn't be
+// visible (e.g. as result of mouse click or touch tap). It already
+// should be doing this automatically, but seems to currently be
+// confused and applies its very visible two-tone outline anyway.
+
+button:focus:not(:focus-visible) {
+  outline: 0;
 }
 
 input,
diff --git a/assets/stylesheets/bootstrap/_root.scss b/assets/stylesheets/bootstrap/_root.scss
index 8110030..ad550df 100644
--- a/assets/stylesheets/bootstrap/_root.scss
+++ b/assets/stylesheets/bootstrap/_root.scss
@@ -1,4 +1,3 @@
-// Do not forget to update getting-started/theming.md!
 :root {
   // Custom variable values only support SassScript inside `#{}`.
   @each $color, $value in $colors {
diff --git a/assets/stylesheets/bootstrap/_spinners.scss b/assets/stylesheets/bootstrap/_spinners.scss
index 27c9241..7d8fba7 100644
--- a/assets/stylesheets/bootstrap/_spinners.scss
+++ b/assets/stylesheets/bootstrap/_spinners.scss
@@ -13,9 +13,9 @@
   vertical-align: text-bottom;
   border: $spinner-border-width solid currentColor;
   border-right-color: transparent;
-  // stylelint-disable-next-line property-blacklist
+  // stylelint-disable-next-line property-disallowed-list
   border-radius: 50%;
-  animation: spinner-border .75s linear infinite;
+  animation: .75s linear infinite spinner-border;
 }
 
 .spinner-border-sm {
@@ -44,13 +44,22 @@
   height: $spinner-height;
   vertical-align: text-bottom;
   background-color: currentColor;
-  // stylelint-disable-next-line property-blacklist
+  // stylelint-disable-next-line property-disallowed-list
   border-radius: 50%;
   opacity: 0;
-  animation: spinner-grow .75s linear infinite;
+  animation: .75s linear infinite spinner-grow;
 }
 
 .spinner-grow-sm {
   width: $spinner-width-sm;
   height: $spinner-height-sm;
 }
+
+@if $enable-prefers-reduced-motion-media-query {
+  @media (prefers-reduced-motion: reduce) {
+    .spinner-border,
+    .spinner-grow {
+      animation-duration: 1.5s;
+    }
+  }
+}
diff --git a/assets/stylesheets/bootstrap/_type.scss b/assets/stylesheets/bootstrap/_type.scss
index 43dde7d..3112a73 100644
--- a/assets/stylesheets/bootstrap/_type.scss
+++ b/assets/stylesheets/bootstrap/_type.scss
@@ -1,4 +1,4 @@
-// stylelint-disable declaration-no-important, selector-list-comma-newline-after
+// stylelint-disable selector-list-comma-newline-after
 
 //
 // Headings
diff --git a/assets/stylesheets/bootstrap/_variables.scss b/assets/stylesheets/bootstrap/_variables.scss
index 3ff0c65..0a260b9 100644
--- a/assets/stylesheets/bootstrap/_variables.scss
+++ b/assets/stylesheets/bootstrap/_variables.scss
@@ -274,7 +274,7 @@ $embed-responsive-aspect-ratios: join(
 // Font, line-height, and color for body text, headings, and more.
 
 // stylelint-disable value-keyword-case
-$font-family-sans-serif:      -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji" !default;
+$font-family-sans-serif:      -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", "Liberation Sans", sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol", "Noto Color Emoji" !default;
 $font-family-monospace:       SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace !default;
 $font-family-base:            $font-family-sans-serif !default;
 // stylelint-enable value-keyword-case
@@ -363,6 +363,7 @@ $table-border-color:          $border-color !default;
 
 $table-head-bg:               $gray-200 !default;
 $table-head-color:            $gray-700 !default;
+$table-th-font-weight:        null !default;
 
 $table-dark-color:            $white !default;
 $table-dark-bg:               $gray-800 !default;
@@ -582,7 +583,7 @@ $custom-select-disabled-bg:         $gray-200 !default;
 $custom-select-bg-size:             8px 10px !default; // In pixels because image dimensions
 $custom-select-indicator-color:     $gray-800 !default;
 $custom-select-indicator:           url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' width='4' height='5' viewBox='0 0 4 5'><path fill='#{$custom-select-indicator-color}' d='M2 0L0 2h4zm0 5L0 3h4z'/></svg>") !default;
-$custom-select-background:          escape-svg($custom-select-indicator) no-repeat right $custom-select-padding-x center / $custom-select-bg-size !default; // Used so we can have multiple background elements (e.g., arrow and feedback icon)
+$custom-select-background:          escape-svg($custom-select-indicator) right $custom-select-padding-x center / $custom-select-bg-size no-repeat !default; // Used so we can have multiple background elements (e.g., arrow and feedback icon)
 
 $custom-select-feedback-icon-padding-right: add(1em * .75, (2 * $custom-select-padding-y * .75) + $custom-select-padding-x + $custom-select-indicator-padding) !default;
 $custom-select-feedback-icon-position:      center right ($custom-select-padding-x + $custom-select-indicator-padding) !default;
@@ -730,6 +731,8 @@ $navbar-toggler-padding-x:          .75rem !default;
 $navbar-toggler-font-size:          $font-size-lg !default;
 $navbar-toggler-border-radius:      $btn-border-radius !default;
 
+$navbar-nav-scroll-max-height:      75vh !default;
+
 $navbar-dark-color:                 rgba($white, .5) !default;
 $navbar-dark-hover-color:           rgba($white, .75) !default;
 $navbar-dark-active-color:          $white !default;
@@ -755,6 +758,7 @@ $navbar-dark-brand-hover-color:           $navbar-dark-active-color !default;
 // Dropdown menu container and contents.
 
 $dropdown-min-width:                10rem !default;
+$dropdown-padding-x:                0 !default;
 $dropdown-padding-y:                .5rem !default;
 $dropdown-spacer:                   .125rem !default;
 $dropdown-font-size:                $font-size-base !default;
@@ -770,12 +774,12 @@ $dropdown-box-shadow:               0 .5rem 1rem rgba($black, .175) !default;
 
 $dropdown-link-color:               $gray-900 !default;
 $dropdown-link-hover-color:         darken($gray-900, 5%) !default;
-$dropdown-link-hover-bg:            $gray-100 !default;
+$dropdown-link-hover-bg:            $gray-200 !default;
 
 $dropdown-link-active-color:        $component-active-color !default;
 $dropdown-link-active-bg:           $component-active-bg !default;
 
-$dropdown-link-disabled-color:      $gray-600 !default;
+$dropdown-link-disabled-color:      $gray-500 !default;
 
 $dropdown-item-padding-y:           .25rem !default;
 $dropdown-item-padding-x:           1.5rem !default;
@@ -814,6 +818,8 @@ $pagination-disabled-color:         $gray-600 !default;
 $pagination-disabled-bg:            $white !default;
 $pagination-disabled-border-color:  $gray-300 !default;
 
+$pagination-border-radius-sm:       $border-radius-sm !default;
+$pagination-border-radius-lg:       $border-radius-lg !default;
 
 // Jumbotron
 
diff --git a/assets/stylesheets/bootstrap/mixins/_border-radius.scss b/assets/stylesheets/bootstrap/mixins/_border-radius.scss
index aee9bf3..4fad91d 100644
--- a/assets/stylesheets/bootstrap/mixins/_border-radius.scss
+++ b/assets/stylesheets/bootstrap/mixins/_border-radius.scss
@@ -1,4 +1,4 @@
-// stylelint-disable property-blacklist
+// stylelint-disable property-disallowed-list
 // Single side border-radius
 
 // Helper function to replace negative values with 0
diff --git a/assets/stylesheets/bootstrap/mixins/_forms.scss b/assets/stylesheets/bootstrap/mixins/_forms.scss
index 39b52f3..a321630 100644
--- a/assets/stylesheets/bootstrap/mixins/_forms.scss
+++ b/assets/stylesheets/bootstrap/mixins/_forms.scss
@@ -64,6 +64,13 @@
     color: color-yiq($color);
     background-color: rgba($color, $form-feedback-tooltip-opacity);
     @include border-radius($form-feedback-tooltip-border-radius);
+
+    // See https://github.com/twbs/bootstrap/pull/31557
+    // Align tooltip to form elements
+    .form-row > .col > &,
+    .form-row > [class*="col-"] > & {
+      left: $form-grid-gutter-width / 2;
+    }
   }
 
   @include form-validation-state-selector($state) {
@@ -108,7 +115,7 @@
 
       @if $enable-validation-icons {
         padding-right: $custom-select-feedback-icon-padding-right;
-        background: $custom-select-background, escape-svg($icon) $custom-select-bg no-repeat $custom-select-feedback-icon-position / $custom-select-feedback-icon-size;
+        background: $custom-select-background, $custom-select-bg escape-svg($icon) $custom-select-feedback-icon-position / $custom-select-feedback-icon-size no-repeat;
       }
 
       &:focus {
diff --git a/assets/stylesheets/bootstrap/mixins/_grid.scss b/assets/stylesheets/bootstrap/mixins/_grid.scss
index b72d150..19babc0 100644
--- a/assets/stylesheets/bootstrap/mixins/_grid.scss
+++ b/assets/stylesheets/bootstrap/mixins/_grid.scss
@@ -62,7 +62,7 @@
 // numberof columns. Supports wrapping to new lines, but does not do a Masonry
 // style grid.
 @mixin row-cols($count) {
-  & > * {
+  > * {
     flex: 0 0 100% / $count;
     max-width: 100% / $count;
   }
diff --git a/assets/stylesheets/bootstrap/mixins/_image.scss b/assets/stylesheets/bootstrap/mixins/_image.scss
index c971e03..3aaa0d7 100644
--- a/assets/stylesheets/bootstrap/mixins/_image.scss
+++ b/assets/stylesheets/bootstrap/mixins/_image.scss
@@ -26,7 +26,7 @@
   // Autoprefixer takes care of adding -webkit-min-device-pixel-ratio and -o-min-device-pixel-ratio,
   // but doesn't convert dppx=>dpi.
   // There's no such thing as unprefixed min-device-pixel-ratio since it's nonstandard.
-  // Compatibility info: https://caniuse.com/#feat=css-media-resolution
+  // Compatibility info: https://caniuse.com/css-media-resolution
   @media only screen and (min-resolution: 192dpi), // IE9-11 don't support dppx
     only screen and (min-resolution: 2dppx) { // Standardized
     background-image: url($file-2x);
diff --git a/assets/stylesheets/bootstrap/mixins/_screen-reader.scss b/assets/stylesheets/bootstrap/mixins/_screen-reader.scss
index 2123039..6913442 100644
--- a/assets/stylesheets/bootstrap/mixins/_screen-reader.scss
+++ b/assets/stylesheets/bootstrap/mixins/_screen-reader.scss
@@ -1,6 +1,6 @@
 // Only display content to screen readers
 //
-// See: https://a11yproject.com/posts/how-to-hide-content/
+// See: https://www.a11yproject.com/posts/2013-01-11-how-to-hide-content/
 // See: https://hugogiraudel.com/2016/10/13/css-hide-and-seek/
 
 @mixin sr-only() {
diff --git a/assets/stylesheets/bootstrap/mixins/_transition.scss b/assets/stylesheets/bootstrap/mixins/_transition.scss
index 54553de..54870bf 100644
--- a/assets/stylesheets/bootstrap/mixins/_transition.scss
+++ b/assets/stylesheets/bootstrap/mixins/_transition.scss
@@ -1,4 +1,4 @@
-// stylelint-disable property-blacklist
+// stylelint-disable property-disallowed-list
 @mixin transition($transition...) {
   @if length($transition) == 0 {
     $transition: $transition-base;
diff --git a/assets/stylesheets/bootstrap/utilities/_borders.scss b/assets/stylesheets/bootstrap/utilities/_borders.scss
index 302f6bf..205f3fc 100644
--- a/assets/stylesheets/bootstrap/utilities/_borders.scss
+++ b/assets/stylesheets/bootstrap/utilities/_borders.scss
@@ -1,4 +1,4 @@
-// stylelint-disable property-blacklist, declaration-no-important
+// stylelint-disable property-disallowed-list, declaration-no-important
 
 //
 // Border
diff --git a/assets/stylesheets/bootstrap/utilities/_text.scss b/assets/stylesheets/bootstrap/utilities/_text.scss
index 5d0f1c8..3a9f83e 100644
--- a/assets/stylesheets/bootstrap/utilities/_text.scss
+++ b/assets/stylesheets/bootstrap/utilities/_text.scss
@@ -63,8 +63,8 @@
 .text-decoration-none { text-decoration: none !important; }
 
 .text-break {
-  word-break: break-word !important; // IE & < Edge 18
-  overflow-wrap: break-word !important;
+  word-break: break-word !important; // Deprecated, but avoids issues with flex containers
+  word-wrap: break-word !important; // Used instead of `overflow-wrap` for IE & Edge Legacy
 }
 
 // Reset