diff --git a/browser/devtools/styleinspector/CssRuleView.jsm b/browser/devtools/styleinspector/CssRuleView.jsm
index 64d92e703ddc..263309513276 100644
--- a/browser/devtools/styleinspector/CssRuleView.jsm
+++ b/browser/devtools/styleinspector/CssRuleView.jsm
@@ -732,8 +732,26 @@ CssRuleView.prototype = {
     }.bind(this);
 
     this._createEditors();
+
+    // When creating a new property, we fake the normal property
+    // editor behavior (focusing a property's value after entering its
+    // name) by responding to the name's blur event, creating the
+    // value editor, and grabbing focus to the value editor.  But if
+    // focus has already moved to another document, we won't be able
+    // to move focus to the new editor.
+    // Create a focusable item at the end of the editors to catch these
+    // cases.
+    this._focusBackstop = createChild(this.element, "div", {
+      tabindex: 0,
+    });
+    this._backstopHandler = function() {
+      // If this item is actually focused long enough to get the focus
+      // event, allow focus to move on out of this document.
+      moveFocus(this.doc.defaultView, FOCUS_FORWARD);
+    }.bind(this);
+    this._focusBackstop.addEventListener("focus", this._backstopHandler, false);
   },
-  
+
   /**
    * Update the rules for the currently highlighted element.
    */
@@ -762,6 +780,12 @@ CssRuleView.prototype = {
     this._clearRules();
     this._viewedElement = null;
     this._elementStyle = null;
+
+    if (this._focusBackstop) {
+      this._focusBackstop.removeEventListener("focus", this._backstopHandler, false);
+      this._backstopHandler = null;
+      this._focusBackstop = null;
+    }
   },
 
   /**
@@ -845,7 +869,6 @@ RuleEditor.prototype = {
 
     this.openBrace = createChild(header, "span", {
       class: "ruleview-ruleopen",
-      tabindex: "0",
       textContent: " {"
     });
 
diff --git a/browser/devtools/styleinspector/test/Makefile.in b/browser/devtools/styleinspector/test/Makefile.in
index 031a9e83eee2..104a4a4f0f2a 100644
--- a/browser/devtools/styleinspector/test/Makefile.in
+++ b/browser/devtools/styleinspector/test/Makefile.in
@@ -60,6 +60,7 @@ _BROWSER_TEST_FILES = \
   browser_ruleview_manipulation.js \
   browser_ruleview_override.js \
   browser_ruleview_ui.js \
+  browser_ruleview_focus.js \
   browser_bug705707_is_content_stylesheet.js \
   browser_bug722196_property_view_media_queries.js \
   browser_bug722196_rule_view_media_queries.js \
diff --git a/browser/devtools/styleinspector/test/browser_ruleview_focus.js b/browser/devtools/styleinspector/test/browser_ruleview_focus.js
new file mode 100644
index 000000000000..188255e4b73e
--- /dev/null
+++ b/browser/devtools/styleinspector/test/browser_ruleview_focus.js
@@ -0,0 +1,106 @@
+/* vim: set ts=2 et sw=2 tw=80: */
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+// Test that focus doesn't leave the style editor when adding a property
+// (bug 719916)
+
+let doc;
+let stylePanel;
+
+function waitForRuleView(aCallback)
+{
+  if (InspectorUI.ruleView) {
+    aCallback();
+    return;
+  }
+
+  let ruleViewFrame = InspectorUI.getToolIframe(InspectorUI.ruleViewObject);
+  ruleViewFrame.addEventListener("load", function(evt) {
+    ruleViewFrame.removeEventListener(evt.type, arguments.callee, true);
+    executeSoon(function() {
+      aCallback();
+    });
+  }, true);
+}
+
+function waitForEditorFocus(aParent, aCallback)
+{
+  aParent.addEventListener("focus", function onFocus(evt) {
+    if (evt.target.inplaceEditor) {
+      aParent.removeEventListener("focus", onFocus, true);
+      let editor = evt.target.inplaceEditor;
+      executeSoon(function() {
+        aCallback(editor);
+      });
+    }
+  }, true);
+}
+
+function openRuleView()
+{
+  Services.obs.addObserver(function onOpened() {
+    Services.obs.removeObserver(onOpened,
+    InspectorUI.INSPECTOR_NOTIFICATIONS.OPENED, false);
+
+    // Highlight a node.
+    let node = content.document.getElementsByTagName("h1")[0];
+    InspectorUI.inspectNode(node);
+    InspectorUI.stopInspecting();
+
+    // Open the rule view sidebar.
+    waitForRuleView(testFocus);
+
+    InspectorUI.showSidebar();
+    InspectorUI.ruleButton.click();
+
+    testFocus();
+  }, InspectorUI.INSPECTOR_NOTIFICATIONS.OPENED, false);
+  InspectorUI.openInspectorUI();
+}
+
+function testFocus()
+{
+  let ruleViewFrame = InspectorUI.getToolIframe(InspectorUI.ruleViewObject);
+  let brace = ruleViewFrame.contentDocument.querySelectorAll(".ruleview-ruleclose")[0];
+  waitForEditorFocus(brace.parentNode, function onNewElement(aEditor) {
+    aEditor.input.value = "color";
+    waitForEditorFocus(brace.parentNode, function onEditingValue(aEditor) {
+      // If we actually get this focus we're ok.
+      ok(true, "We got focus.");
+      aEditor.input.value = "green";
+
+      // If we've retained focus, pressing return will start a new editor.
+      // If not, we'll wait here until we time out.
+      waitForEditorFocus(brace.parentNode, function onNewEditor(aEditor) {
+        aEditor.input.blur();
+        finishTest();
+      });
+      EventUtils.sendKey("return");
+    });
+    EventUtils.sendKey("return");
+  });
+
+  brace.focus();
+}
+
+function finishUp()
+{
+  doc = stylePanel = null;
+  gBrowser.removeCurrentTab();
+  finish();
+}
+
+function test()
+{
+  waitForExplicitFinish();
+  gBrowser.selectedTab = gBrowser.addTab();
+  gBrowser.selectedBrowser.addEventListener("load", function(evt) {
+    gBrowser.selectedBrowser.removeEventListener(evt.type, arguments.callee, true);
+    doc = content.document;
+    doc.title = "Rule View Test";
+    waitForFocus(openRuleView, content);
+  }, true);
+
+  content.location = "data:text/html,<h1>Some header text</h1>";
+}