fix a performance bug with tab throbbers.

JS/animateContextMenus.uc.js

@@ -1,6 +1,6 @@
 // ==UserScript==
 // @name           Animate Context Menus
-// @version        1.0
+// @version        1.0.1
 // @author         aminomancer
 // @homepage       https://github.com/aminomancer/uc.css.js
 // @description    Give all context menus the same opening animation that panel popups like the app menu have — the menu slides down 70px and fades in opacity at the same time. It's a cool effect that doesn't trigger a reflow since it uses transform, but it does repaint the menu, so I wouldn't recommend using this on weak hardware.
@@ -40,6 +40,7 @@ class AnimateContextMenus {
     pointer-events: none;
 }
 `;
+        const { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
         let sss = Cc["@mozilla.org/content/style-sheet-service;1"].getService(
             Ci.nsIStyleSheetService
         );

uc-tabs.css

@@ -688,6 +688,11 @@ so in other words it won't show if audio is playing until you hover the general
     transform: translateX(25px) scale(0.5) !important;
 }
 
+.tabbrowser-tab .tab-label:not([fadein]),
+.tabbrowser-tab .tab-throbber:not([fadein]) {
+    display: none !important;
+}
+
 .tabbrowser-tab .tab-throbber:not([busy], [progress]) {
     opacity: 0 !important;
     pointer-events: none !important;
@@ -718,7 +723,7 @@ so in other words it won't show if audio is playing until you hover the general
         }
     }
 
-    .tab-throbber {
+    .tab-throbber[fadein] {
         display: block !important;
         position: relative !important;
     }