Bug 613763 - Form elements can regain focus under a tab-modal prompt. r=enn, a=blocking

browser/base/content/browser.css

@@ -475,3 +475,7 @@ window[chromehidden~="toolbar"] toolbar:not(.toolbar-primary):not(.chromeclass-m
 #status-bar > .statusbar-resizerpanel {
   display: none;
 }
+
+browser[tabmodalPromptShowing] {
+  -moz-user-focus: none !important;
+}

toolkit/components/prompts/src/nsPrompter.js

@@ -422,7 +422,14 @@ function openTabPrompt(domWin, tabPrompt, args) {
         callbackInvoked = true;
         if (newPrompt)
             tabPrompt.removePrompt(newPrompt);
+
         winUtils.leaveModalState();
+
+        // Restore focus to the previously focused element within tab.
+        let fm = Cc["@mozilla.org/focus-manager;1"].
+                 getService(Ci.nsIFocusManager);
+        let e = fm.getFocusedElementForWindow(domWin.top, false, {});
+        fm.setFocus(e, fm.FLAG_NOSCROLL);
     }
 
     let newPrompt;