diff --git a/static/css/bootstrap.css b/static/css/bootstrap.css
index 1fea76b6..c7da5787 100644
--- a/static/css/bootstrap.css
+++ b/static/css/bootstrap.css
@@ -253,14 +253,10 @@ th {
   }
 }
 * {
-  -webkit-box-sizing: border-box;
-  -moz-box-sizing: border-box;
   box-sizing: border-box;
 }
 *:before,
 *:after {
-  -webkit-box-sizing: border-box;
-  -moz-box-sizing: border-box;
   box-sizing: border-box;
 }
 html {
@@ -316,8 +312,6 @@ img {
   background-color: var(--body-bg);
   border: 1px solid #ddd;
   border-radius: 2px;
-  -webkit-transition: all 0.2s ease-in-out;
-  -o-transition: all 0.2s ease-in-out;
   transition: all 0.2s ease-in-out;
   display: inline-block;
   max-width: 100%;
@@ -1784,8 +1778,6 @@ label {
   font-weight: bold;
 }
 input[type="search"] {
-  -webkit-box-sizing: border-box;
-  -moz-box-sizing: border-box;
   box-sizing: border-box;
 }
 input[type="radio"],
@@ -1831,24 +1823,19 @@ output {
   background-image: none;
   border: 1px solid var(--input-border);
   border-radius: 2px;
-  -webkit-box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075);
   box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075);
 }
 .form-control:focus {
   border-color: #66afe9;
   outline: 0;
-  -webkit-box-shadow: inset 0 1px 1px rgba(0,0,0,.075), 0 0 0 4px rgba(102, 175, 233, 0.2);
   box-shadow: inset 0 1px 1px rgba(0,0,0,.075), 0 0 0 4px rgba(102, 175, 233, 0.2);
 }
-.form-control::-moz-placeholder {
-  color: var(--text-muted);
-  opacity: 1;
-}
 .form-control:-ms-input-placeholder {
   color: var(--text-muted);
 }
-.form-control::-webkit-input-placeholder {
+.form-control::placeholder {
   color: var(--text-muted);
+  opacity: 1;
 }
 .form-control::-ms-expand {
   border: 0;
@@ -2094,12 +2081,10 @@ select[multiple].input-lg {
 }
 .has-success .form-control {
   border-color: #3c763d;
-  -webkit-box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075);
   box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075);
 }
 .has-success .form-control:focus {
   border-color: #2b542c;
-  -webkit-box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075), 0 0 0 4px rgba(60, 118, 61, 0.2);
   box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075), 0 0 0 4px rgba(60, 118, 61, 0.2);
 }
 .has-success .input-group-addon {
@@ -2124,12 +2109,10 @@ select[multiple].input-lg {
 }
 .has-warning .form-control {
   border-color: #8a6d3b;
-  -webkit-box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075);
   box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075);
 }
 .has-warning .form-control:focus {
   border-color: #66512c;
-  -webkit-box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075), 0 0 0 4px rgba(138, 109, 59, 0.2);
   box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075), 0 0 0 4px rgba(138, 109, 59, 0.2);
 }
 .has-warning .input-group-addon {
@@ -2154,12 +2137,10 @@ select[multiple].input-lg {
 }
 .has-error .form-control {
   border-color: #a94442;
-  -webkit-box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075);
   box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075);
 }
 .has-error .form-control:focus {
   border-color: #843534;
-  -webkit-box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075), 0 0 0 4px rgba(169, 68, 66, 0.2);
   box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075), 0 0 0 4px rgba(169, 68, 66, 0.2);
 }
 .has-error .input-group-addon {
@@ -2310,7 +2291,6 @@ select[multiple].input-lg {
 .btn.active {
   outline: 0;
   background-image: none;
-  -webkit-box-shadow: inset 0 3px 5px rgba(0, 0, 0, 0.125);
   box-shadow: inset 0 3px 5px rgba(0, 0, 0, 0.125);
 }
 .btn.disabled,
@@ -2318,7 +2298,6 @@ select[multiple].input-lg {
 fieldset[disabled] .btn {
   cursor: not-allowed;
   opacity: 0.65;
-  -webkit-box-shadow: none;
   box-shadow: none;
 }
 a.btn.disabled,
@@ -2678,7 +2657,6 @@ fieldset[disabled] .btn-danger.focus {
 .btn-link[disabled],
 fieldset[disabled] .btn-link {
   background-color: transparent;
-  -webkit-box-shadow: none;
   box-shadow: none;
 }
 .btn-link,
@@ -2735,8 +2713,6 @@ input[type="button"].btn-block {
 }
 .fade {
   opacity: 0;
-  -webkit-transition: opacity 0.15s linear;
-  -o-transition: opacity 0.15s linear;
   transition: opacity 0.15s linear;
 }
 .fade.in {
@@ -2758,11 +2734,8 @@ tbody.collapse.in {
   position: relative;
   height: 0;
   overflow: hidden;
-  -webkit-transition-property: height, visibility;
   transition-property: height, visibility;
-  -webkit-transition-duration: 0.35s;
   transition-duration: 0.35s;
-  -webkit-transition-timing-function: ease;
   transition-timing-function: ease;
 }
 .caret {
@@ -2800,7 +2773,6 @@ tbody.collapse.in {
   border: 1px solid #ccc;
   border: 1px solid rgba(0, 0, 0, 0.15);
   border-radius: 2px;
-  -webkit-box-shadow: 0 6px 12px rgba(0, 0, 0, 0.175);
   box-shadow: 0 6px 12px rgba(0, 0, 0, 0.175);
   background-clip: padding-box;
 }
@@ -2989,11 +2961,9 @@ tbody.collapse.in {
   padding-right: 12px;
 }
 .btn-group.open .dropdown-toggle {
-  -webkit-box-shadow: inset 0 3px 5px rgba(0, 0, 0, 0.125);
   box-shadow: inset 0 3px 5px rgba(0, 0, 0, 0.125);
 }
 .btn-group.open .dropdown-toggle.btn-link {
-  -webkit-box-shadow: none;
   box-shadow: none;
 }
 .btn .caret {
@@ -4177,7 +4147,6 @@ button.list-group-item-danger.active:focus {
   background-color: var(--panel-bg);
   border: 1px solid transparent;
   border-radius: 2px;
-  -webkit-box-shadow: 0 1px 1px rgba(0, 0, 0, 0.05);
   box-shadow: 0 1px 1px rgba(0, 0, 0, 0.05);
 }
 .panel-body {
@@ -4554,19 +4523,10 @@ button.close {
   outline: 0;
 }
 .modal.fade .modal-dialog {
-  -webkit-transform: translate(0, -25%);
-  -ms-transform: translate(0, -25%);
-  -o-transform: translate(0, -25%);
   transform: translate(0, -25%);
-  -webkit-transition: -webkit-transform 0.3s ease-out;
-  -moz-transition: -moz-transform 0.3s ease-out;
-  -o-transition: -o-transform 0.3s ease-out;
   transition: transform 0.3s ease-out;
 }
 .modal.in .modal-dialog {
-  -webkit-transform: translate(0, 0);
-  -ms-transform: translate(0, 0);
-  -o-transform: translate(0, 0);
   transform: translate(0, 0);
 }
 .modal-open .modal {
@@ -4584,7 +4544,6 @@ button.close {
   border: 1px solid #999;
   border: 1px solid rgba(0, 0, 0, 0.2);
   border-radius: 3px;
-  -webkit-box-shadow: 0 3px 9px rgba(0, 0, 0, 0.5);
   box-shadow: 0 3px 9px rgba(0, 0, 0, 0.5);
   background-clip: padding-box;
   outline: 0;
@@ -4647,7 +4606,6 @@ button.close {
     margin: 30px auto;
   }
   .modal-content {
-    -webkit-box-shadow: 0 5px 15px rgba(0, 0, 0, 0.5);
     box-shadow: 0 5px 15px rgba(0, 0, 0, 0.5);
   }
   .modal-sm {
diff --git a/stuff/bootstrap/mixins/vendor-prefixes.less b/stuff/bootstrap/mixins/vendor-prefixes.less
index 2b5e74b9..2358a50a 100644
--- a/stuff/bootstrap/mixins/vendor-prefixes.less
+++ b/stuff/bootstrap/mixins/vendor-prefixes.less
@@ -66,14 +66,11 @@
 // supported browsers that have box shadow capabilities now support it.
 
 .box-shadow(@shadow) {
-  -webkit-box-shadow: @shadow; // iOS <4.3 & Android <4.1
           box-shadow: @shadow;
 }
 
 // Box sizing
 .box-sizing(@boxmodel) {
-  -webkit-box-sizing: @boxmodel;
-     -moz-box-sizing: @boxmodel;
           box-sizing: @boxmodel;
 }
 
@@ -99,72 +96,40 @@
 
 // Placeholder text
 .placeholder(@color: @input-color-placeholder) {
-  // Firefox
-  &::-moz-placeholder {
-    color: @color;
-    opacity: 1; // Override Firefox's unusual default opacity; see https://github.com/twbs/bootstrap/pull/11526
-  }
   &:-ms-input-placeholder { color: @color; } // Internet Explorer 10+
-  &::-webkit-input-placeholder  { color: @color; } // Safari and Chrome
+  &::placeholder  { color: @color; opacity: 1; }
 }
 
 // Transformations
 .scale(@ratio) {
-  -webkit-transform: scale(@ratio);
-      -ms-transform: scale(@ratio); // IE9 only
-       -o-transform: scale(@ratio);
           transform: scale(@ratio);
 }
 .scale(@ratioX; @ratioY) {
-  -webkit-transform: scale(@ratioX, @ratioY);
-      -ms-transform: scale(@ratioX, @ratioY); // IE9 only
-       -o-transform: scale(@ratioX, @ratioY);
           transform: scale(@ratioX, @ratioY);
 }
 .scaleX(@ratio) {
-  -webkit-transform: scaleX(@ratio);
-      -ms-transform: scaleX(@ratio); // IE9 only
-       -o-transform: scaleX(@ratio);
           transform: scaleX(@ratio);
 }
 .scaleY(@ratio) {
   -webkit-transform: scaleY(@ratio);
-      -ms-transform: scaleY(@ratio); // IE9 only
-       -o-transform: scaleY(@ratio);
           transform: scaleY(@ratio);
 }
 .skew(@x; @y) {
-  -webkit-transform: skewX(@x) skewY(@y);
-      -ms-transform: skewX(@x) skewY(@y); // See https://github.com/twbs/bootstrap/issues/4885; IE9+
-       -o-transform: skewX(@x) skewY(@y);
           transform: skewX(@x) skewY(@y);
 }
 .translate(@x; @y) {
-  -webkit-transform: translate(@x, @y);
-      -ms-transform: translate(@x, @y); // IE9 only
-       -o-transform: translate(@x, @y);
           transform: translate(@x, @y);
 }
 .translate3d(@x; @y; @z) {
-  -webkit-transform: translate3d(@x, @y, @z);
           transform: translate3d(@x, @y, @z);
 }
 .rotate(@degrees) {
-  -webkit-transform: rotate(@degrees);
-      -ms-transform: rotate(@degrees); // IE9 only
-       -o-transform: rotate(@degrees);
           transform: rotate(@degrees);
 }
 .rotateX(@degrees) {
-  -webkit-transform: rotateX(@degrees);
-      -ms-transform: rotateX(@degrees); // IE9 only
-       -o-transform: rotateX(@degrees);
           transform: rotateX(@degrees);
 }
 .rotateY(@degrees) {
-  -webkit-transform: rotateY(@degrees);
-      -ms-transform: rotateY(@degrees); // IE9 only
-       -o-transform: rotateY(@degrees);
           transform: rotateY(@degrees);
 }
 .perspective(@perspective) {
@@ -178,9 +143,6 @@
           perspective-origin: @perspective;
 }
 .transform-origin(@origin) {
-  -webkit-transform-origin: @origin;
-     -moz-transform-origin: @origin;
-      -ms-transform-origin: @origin; // IE9 only
           transform-origin: @origin;
 }
 
@@ -188,30 +150,21 @@
 // Transitions
 
 .transition(@transition) {
-  -webkit-transition: @transition;
-       -o-transition: @transition;
           transition: @transition;
 }
 .transition-property(@transition-property) {
-  -webkit-transition-property: @transition-property;
           transition-property: @transition-property;
 }
 .transition-delay(@transition-delay) {
-  -webkit-transition-delay: @transition-delay;
           transition-delay: @transition-delay;
 }
 .transition-duration(@transition-duration) {
-  -webkit-transition-duration: @transition-duration;
           transition-duration: @transition-duration;
 }
 .transition-timing-function(@timing-function) {
-  -webkit-transition-timing-function: @timing-function;
           transition-timing-function: @timing-function;
 }
 .transition-transform(@transition) {
-  -webkit-transition: -webkit-transform @transition;
-     -moz-transition: -moz-transform @transition;
-       -o-transition: -o-transform @transition;
           transition: transform @transition;
 }