bring back global style rules for thin scrollbars (also FF now!)

Author: bwindels

res/css/structures/_AutoHideScrollbar.scss

@@ -14,34 +14,54 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
+// make any scrollbar grey and thin
+html {
+ scrollbar-color: $scrollbar-thumb-color $scrollbar-track-color;
+}
+// scrollbar-width is not inherited (but -color is, why?!),
+// so declare it on every element
+* {
+ scrollbar-width: thin;
+}
+
+::-webkit-scrollbar {
+ width: 6px;
+ height: 6px;
+ background-color: $scrollbar-track-color;
+}
+
+::-webkit-scrollbar-thumb {
+ border-radius: 3px;
+ background-color: $scrollbar-thumb-color;
+}
+
+// make auto-hide scrollbars not transparent again on hover
+.mx_AutoHideScrollbar:hover {
+ scrollbar-color: $scrollbar-thumb-color $scrollbar-track-color;
+
+ &::-webkit-scrollbar {
+ background-color: $scrollbar-track-color;
+ }
+
+ &::-webkit-scrollbar-thumb {
+ background-color: $scrollbar-thumb-color;
+ }
+}
+
+// make scrollbars transparent for autohide scrollbars
 .mx_AutoHideScrollbar {
  overflow-x: hidden;
  overflow-y: auto;
  overflow-y: overlay; // where supported
  -ms-overflow-style: -ms-autohiding-scrollbar;
 
  &::-webkit-scrollbar {
- width: 6px;
- height: 6px;
  background-color: transparent;
  }
 
  &::-webkit-scrollbar-thumb {
- border-radius: 3px;
  background-color: transparent;
  }
 
  scrollbar-color: transparent transparent;
- scrollbar-width: thin;
-}
-
-.mx_AutoHideScrollbar:hover {
- &::-webkit-scrollbar {
- background-color: $scrollbar-track-color;
- }
-
- &::-webkit-scrollbar-thumb {
- background-color: $scrollbar-thumb-color;
- }
- scrollbar-color: $scrollbar-thumb-color $scrollbar-track-color;
 }