fix(loading): reduce memory usage by innactive loading spinner Closes #3454

Author: perrygovier

Diff for: scss/_loading.scss

@@ -21,7 +21,8 @@
   visibility: hidden;
   opacity: 0;
 
-  &:not(.visible) .icon {
+  &:not(.visible) .icon,
+  &:not(.visible) .spinner{
     display: none;
   }
   &.visible {