Bug 977796 - [Australis] Disable subpixel AA on all labels during customize mode transition for Windows. r=jaws, a=sledru.
authorMike Conley <mconley@mozilla.com>
Wed, 26 Feb 2014 16:42:18 -0500
changeset 183102 306e5fffe72b67dbe9e387e438fd63e7b2921d2f
parent 183101 d0f17f5479ac3a4f3c68c47023877cbdb47d1ac5
child 183103 547b83e590a657c5db4625d2c061b516bf7c79fd
push id3343
push userffxbld
push dateMon, 17 Mar 2014 21:55:32 +0000
treeherdermozilla-beta@2f7d3415f79f [default view] [failures only]
perfherder[talos] [build metrics] [platform microbench] (compared to previous push)
reviewersjaws, sledru
bugs977796
milestone29.0a2
Bug 977796 - [Australis] Disable subpixel AA on all labels during customize mode transition for Windows. r=jaws, a=sledru.
browser/themes/windows/browser.css
--- a/browser/themes/windows/browser.css
+++ b/browser/themes/windows/browser.css
@@ -2487,16 +2487,26 @@ chatbox {
   border-top-left-radius: 2.5px;
   border-top-right-radius: 2.5px;
 }
 
 /* Customization mode */
 
 %include ../shared/customizableui/customizeMode.inc.css
 
+/**
+ * This next rule is a hack to disable subpixel anti-aliasing on all
+ * labels during the customize mode transition. Subpixel anti-aliasing
+ * on Windows with Direct2D layers acceleration is particularly slow to
+ * paint, so this hack is how we sidestep that performance bottleneck.
+ */
+#main-window:-moz-any([customize-entering],[customize-exiting]) label {
+  transform: perspective(0.01px);
+}
+
 #main-window[customize-entered] {
   background-image: url("chrome://browser/skin/customizableui/customizeMode-gridTexture.png");
   background-attachment: fixed;
 }
 
 #customization-container {
   border-left: 1px solid @toolbarShadowColor@;
   border-right: 1px solid @toolbarShadowColor@;