--- a/mobile/chrome/content/browser-ui.js
+++ b/mobile/chrome/content/browser-ui.js
@@ -58,16 +58,17 @@ Cu.import("resource://gre/modules/AddonM
 /**
  * Cache of commonly used elements.
  */
 let Elements = {};
 
 [
   ["contentShowing",     "bcast_contentShowing"],
   ["urlbarState",        "bcast_urlbarState"],
+  ["mainKeyset",         "mainKeyset"],
   ["stack",              "stack"],
   ["tabList",            "tabs"],
   ["tabs",               "tabs-container"],
   ["controls",           "browser-controls"],
   ["panelUI",            "panel-container"],
   ["toolbarContainer",   "toolbar-container"],
   ["browsers",           "browsers"],
   ["contentViewport",    "content-viewport"],
@@ -940,19 +941,19 @@ var BrowserUI = {
         }
         break;
       }
       case "SizeChanged":
         this.sizeControls(ViewableAreaObserver.width, ViewableAreaObserver.height);
         break;
       // Window events
       case "keypress":
-        // Ignore events headed toward the browser; they will be
-        // re-dispatched after content has a chance to handle them.
-        if (aEvent.target.localName == "browser")
+        // Ignore events re-dispatched from content; we already
+        // handled them when they were originally fired.
+        if (aEvent.target == Elements.mainKeyset)
           break;
         if (aEvent.keyCode == aEvent.DOM_VK_ESCAPE)
           this.handleEscape(aEvent);
         break;
       case "AppCommand":
         aEvent.stopPropagation();
         switch (aEvent.command) {
           case "Menu":

--- a/mobile/chrome/content/browser.js
+++ b/mobile/chrome/content/browser.js
@@ -1231,17 +1231,17 @@ var Browser = {
         setTimeout(function(self) {
           let tab = self.getTabForBrowser(browser);
           self._doCloseTab(tab);
         }, 0, this);
         break;
       }
 
       case "Browser:KeyPress": {
-        let keyset = document.getElementById("mainKeyset");
+        let keyset = Elements.mainKeyset;
         keyset.setAttribute("disabled", "false");
         if (json.preventDefault)
           break;
 
         let event = document.createEvent("KeyEvents");
         event.initKeyEvent("keypress", true, true, null,
                            json.ctrlKey, json.altKey, json.shiftKey, json.metaKey,
                            json.keyCode, json.charCode);