Reduce motion for boost animation (tootsuite pr #5871)

app/javascript/flavours/glitch/styles/components/index.scss

@@ -556,6 +556,10 @@
   white-space: pre-wrap;
   padding-top: 5px;
 
+  &:focus {
+    outline: 0;
+  }
+
   &.status__content--with-spoiler {
     white-space: normal;
 
@@ -2368,7 +2372,7 @@
 
 @import 'boost';
 
-button.icon-button i.fa-retweet {
+.no-reduce-motion button.icon-button i.fa-retweet {
   background-position: 0 0;
   height: 19px;
   transition: background-position 0.9s steps(10);
@@ -2381,11 +2385,20 @@ button.icon-button i.fa-retweet {
   }
 }
 
-button.icon-button.active i.fa-retweet {
+.no-reduce-motion button.icon-button.active i.fa-retweet {
   transition-duration: 0.9s;
   background-position: 0 100%;
 }
 
+.reduce-motion button.icon-button i.fa-retweet {
+  color: $ui-base-lighter-color;
+  transition: color 100ms ease-in;
+}
+
+.reduce-motion button.icon-button.active i.fa-retweet {
+  color: $ui-highlight-color;
+}
+
 .status-card {
   display: flex;
   cursor: pointer;