Bug 1389860 - tab text color adjustments for Yosemite and higher. Increase tab height (all OS versions). r=Gijs.

toolkit/themes/osx/global/tabbox.css

@@ -35,6 +35,7 @@ tabbox > tabs {
 
 tab {
   -moz-appearance: tab;
+  padding-top: 1px;
 }
 
 tab:-moz-focusring {
@@ -50,9 +51,15 @@ tab:last-of-type {
   padding-inline-end: 2px;
 }
 
-tab[visuallyselected="true"] {
+tab[visuallyselected="true"]:not(:-moz-window-inactive) {
   color: #FFF;
-  text-shadow: rgba(0, 0, 0, 0.4) 0 1px;
+}
+
+@media not all and (-moz-mac-yosemite-theme) {
+  tab[visuallyselected="true"] {
+    color: #FFF;
+    text-shadow: rgba(0, 0, 0, 0.4) 0 1px;
+  }
 }
 
 .tab-middle {