323265 Disabled <input type="image"> has opaque/white background in Camino. Patch by Chris Lawson <bugzilla@chrislawson.net>. r=smorgan sr=smfr a/1.8.1=josh. 322828 File upload widget flickers when styled with font size. Patch by Wevah <mozilla@derailer.org>. r=sardisson sr=smfr a/1.8.1=josh

layout/style/forms.css

@@ -690,4 +690,14 @@ input[type="file"] > input[type="button"] {
   margin: 0px 0px 2px 5px !important;
 }
 
+/* make sure disabled images have transparent background */
+input[type="image"][disabled] {
+  background-color: transparent;
+}
+
+/* avoid flickering size when file selector buttons with large text are activated */
+input[type="file"] > input[type="button"]:active:hover {
+  font-size: inherit;
+}
+
 %endif