--- a/browser/devtools/markupview/test/browser_markupview_events_jquery_1.0.js
+++ b/browser/devtools/markupview/test/browser_markupview_events_jquery_1.0.js
@@ -71,30 +71,34 @@ const TEST_DATA = [
                  "    alert(7);\n" +
                  "  };\n" +
                  "  var handler8 = function divClick2() {\n" +
                  "    alert(8);\n" +
                  "  };\n" +
                  "  var handler9 = function divKeyDown() {\n" +
                  "    alert(9);\n" +
                  "  };\n" +
+                 "  var handler10 = function divDragOut() {\n" +
+                 "    alert(10);\n" +
+                 "  };\n" +
                  "\n" +
                  "  if ($(\"#livediv\").live) {\n" +
                  "    $(\"#livediv\").live(\"dblclick\", handler1);\n" +
                  "    $(\"#livediv\").live(\"dragstart\", handler2);\n" +
                  "  }\n" +
                  "\n" +
                  "  if ($(\"#livediv\").delegate) {\n" +
                  "    $(document).delegate(\"#livediv\", \"dragleave\", handler3);\n" +
                  "    $(document).delegate(\"#livediv\", \"dragend\", handler4);\n" +
                  "  }\n" +
                  "\n" +
                  "  if ($(\"#livediv\").on) {\n" +
                  "    $(document).on(\"drop\", \"#livediv\", handler5);\n" +
                  "    $(document).on(\"dragover\", \"#livediv\", handler6);\n" +
+                 "    $(document).on(\"dragout\", \"#livediv:xxxxx\", handler10);\n" +
                  "  }\n" +
                  "\n" +
                  "  var div = $(\"div\")[0];\n" +
                  "  $(div).click(handler7);\n" +
                  "  $(div).click(handler8);\n" +
                  "  $(div).keydown(handler9);\n" +
                  "}"
       },

--- a/browser/devtools/markupview/test/browser_markupview_events_jquery_1.1.js
+++ b/browser/devtools/markupview/test/browser_markupview_events_jquery_1.1.js
@@ -75,30 +75,34 @@ const TEST_DATA = [
                  "    alert(7);\n" +
                  "  };\n" +
                  "  var handler8 = function divClick2() {\n" +
                  "    alert(8);\n" +
                  "  };\n" +
                  "  var handler9 = function divKeyDown() {\n" +
                  "    alert(9);\n" +
                  "  };\n" +
+                 "  var handler10 = function divDragOut() {\n" +
+                 "    alert(10);\n" +
+                 "  };\n" +
                  "\n" +
                  "  if ($(\"#livediv\").live) {\n" +
                  "    $(\"#livediv\").live(\"dblclick\", handler1);\n" +
                  "    $(\"#livediv\").live(\"dragstart\", handler2);\n" +
                  "  }\n" +
                  "\n" +
                  "  if ($(\"#livediv\").delegate) {\n" +
                  "    $(document).delegate(\"#livediv\", \"dragleave\", handler3);\n" +
                  "    $(document).delegate(\"#livediv\", \"dragend\", handler4);\n" +
                  "  }\n" +
                  "\n" +
                  "  if ($(\"#livediv\").on) {\n" +
                  "    $(document).on(\"drop\", \"#livediv\", handler5);\n" +
                  "    $(document).on(\"dragover\", \"#livediv\", handler6);\n" +
+                 "    $(document).on(\"dragout\", \"#livediv:xxxxx\", handler10);\n" +
                  "  }\n" +
                  "\n" +
                  "  var div = $(\"div\")[0];\n" +
                  "  $(div).click(handler7);\n" +
                  "  $(div).click(handler8);\n" +
                  "  $(div).keydown(handler9);\n" +
                  "}"
       },

--- a/browser/devtools/markupview/test/browser_markupview_events_jquery_1.11.1.js
+++ b/browser/devtools/markupview/test/browser_markupview_events_jquery_1.11.1.js
@@ -46,30 +46,34 @@ const TEST_DATA = [
                  "    alert(7);\n" +
                  "  };\n" +
                  "  var handler8 = function divClick2() {\n" +
                  "    alert(8);\n" +
                  "  };\n" +
                  "  var handler9 = function divKeyDown() {\n" +
                  "    alert(9);\n" +
                  "  };\n" +
+                 "  var handler10 = function divDragOut() {\n" +
+                 "    alert(10);\n" +
+                 "  };\n" +
                  "\n" +
                  "  if ($(\"#livediv\").live) {\n" +
                  "    $(\"#livediv\").live(\"dblclick\", handler1);\n" +
                  "    $(\"#livediv\").live(\"dragstart\", handler2);\n" +
                  "  }\n" +
                  "\n" +
                  "  if ($(\"#livediv\").delegate) {\n" +
                  "    $(document).delegate(\"#livediv\", \"dragleave\", handler3);\n" +
                  "    $(document).delegate(\"#livediv\", \"dragend\", handler4);\n" +
                  "  }\n" +
                  "\n" +
                  "  if ($(\"#livediv\").on) {\n" +
                  "    $(document).on(\"drop\", \"#livediv\", handler5);\n" +
                  "    $(document).on(\"dragover\", \"#livediv\", handler6);\n" +
+                 "    $(document).on(\"dragout\", \"#livediv:xxxxx\", handler10);\n" +
                  "  }\n" +
                  "\n" +
                  "  var div = $(\"div\")[0];\n" +
                  "  $(div).click(handler7);\n" +
                  "  $(div).click(handler8);\n" +
                  "  $(div).keydown(handler9);\n" +
                  "}"
       }

--- a/browser/devtools/markupview/test/browser_markupview_events_jquery_1.2.js
+++ b/browser/devtools/markupview/test/browser_markupview_events_jquery_1.2.js
@@ -46,30 +46,34 @@ const TEST_DATA = [
                  "    alert(7);\n" +
                  "  };\n" +
                  "  var handler8 = function divClick2() {\n" +
                  "    alert(8);\n" +
                  "  };\n" +
                  "  var handler9 = function divKeyDown() {\n" +
                  "    alert(9);\n" +
                  "  };\n" +
+                 "  var handler10 = function divDragOut() {\n" +
+                 "    alert(10);\n" +
+                 "  };\n" +
                  "\n" +
                  "  if ($(\"#livediv\").live) {\n" +
                  "    $(\"#livediv\").live(\"dblclick\", handler1);\n" +
                  "    $(\"#livediv\").live(\"dragstart\", handler2);\n" +
                  "  }\n" +
                  "\n" +
                  "  if ($(\"#livediv\").delegate) {\n" +
                  "    $(document).delegate(\"#livediv\", \"dragleave\", handler3);\n" +
                  "    $(document).delegate(\"#livediv\", \"dragend\", handler4);\n" +
                  "  }\n" +
                  "\n" +
                  "  if ($(\"#livediv\").on) {\n" +
                  "    $(document).on(\"drop\", \"#livediv\", handler5);\n" +
                  "    $(document).on(\"dragover\", \"#livediv\", handler6);\n" +
+                 "    $(document).on(\"dragout\", \"#livediv:xxxxx\", handler10);\n" +
                  "  }\n" +
                  "\n" +
                  "  var div = $(\"div\")[0];\n" +
                  "  $(div).click(handler7);\n" +
                  "  $(div).click(handler8);\n" +
                  "  $(div).keydown(handler9);\n" +
                  "}"
       },

--- a/browser/devtools/markupview/test/browser_markupview_events_jquery_1.3.js
+++ b/browser/devtools/markupview/test/browser_markupview_events_jquery_1.3.js
@@ -76,30 +76,34 @@ const TEST_DATA = [
                  "    alert(7);\n" +
                  "  };\n" +
                  "  var handler8 = function divClick2() {\n" +
                  "    alert(8);\n" +
                  "  };\n" +
                  "  var handler9 = function divKeyDown() {\n" +
                  "    alert(9);\n" +
                  "  };\n" +
+                 "  var handler10 = function divDragOut() {\n" +
+                 "    alert(10);\n" +
+                 "  };\n" +
                  "\n" +
                  "  if ($(\"#livediv\").live) {\n" +
                  "    $(\"#livediv\").live(\"dblclick\", handler1);\n" +
                  "    $(\"#livediv\").live(\"dragstart\", handler2);\n" +
                  "  }\n" +
                  "\n" +
                  "  if ($(\"#livediv\").delegate) {\n" +
                  "    $(document).delegate(\"#livediv\", \"dragleave\", handler3);\n" +
                  "    $(document).delegate(\"#livediv\", \"dragend\", handler4);\n" +
                  "  }\n" +
                  "\n" +
                  "  if ($(\"#livediv\").on) {\n" +
                  "    $(document).on(\"drop\", \"#livediv\", handler5);\n" +
                  "    $(document).on(\"dragover\", \"#livediv\", handler6);\n" +
+                 "    $(document).on(\"dragout\", \"#livediv:xxxxx\", handler10);\n" +
                  "  }\n" +
                  "\n" +
                  "  var div = $(\"div\")[0];\n" +
                  "  $(div).click(handler7);\n" +
                  "  $(div).click(handler8);\n" +
                  "  $(div).keydown(handler9);\n" +
                  "}"
       },

--- a/browser/devtools/markupview/test/browser_markupview_events_jquery_1.4.js
+++ b/browser/devtools/markupview/test/browser_markupview_events_jquery_1.4.js
@@ -46,30 +46,34 @@ const TEST_DATA = [
                  "    alert(7);\n" +
                  "  };\n" +
                  "  var handler8 = function divClick2() {\n" +
                  "    alert(8);\n" +
                  "  };\n" +
                  "  var handler9 = function divKeyDown() {\n" +
                  "    alert(9);\n" +
                  "  };\n" +
+                 "  var handler10 = function divDragOut() {\n" +
+                 "    alert(10);\n" +
+                 "  };\n" +
                  "\n" +
                  "  if ($(\"#livediv\").live) {\n" +
                  "    $(\"#livediv\").live(\"dblclick\", handler1);\n" +
                  "    $(\"#livediv\").live(\"dragstart\", handler2);\n" +
                  "  }\n" +
                  "\n" +
                  "  if ($(\"#livediv\").delegate) {\n" +
                  "    $(document).delegate(\"#livediv\", \"dragleave\", handler3);\n" +
                  "    $(document).delegate(\"#livediv\", \"dragend\", handler4);\n" +
                  "  }\n" +
                  "\n" +
                  "  if ($(\"#livediv\").on) {\n" +
                  "    $(document).on(\"drop\", \"#livediv\", handler5);\n" +
                  "    $(document).on(\"dragover\", \"#livediv\", handler6);\n" +
+                 "    $(document).on(\"dragout\", \"#livediv:xxxxx\", handler10);\n" +
                  "  }\n" +
                  "\n" +
                  "  var div = $(\"div\")[0];\n" +
                  "  $(div).click(handler7);\n" +
                  "  $(div).click(handler8);\n" +
                  "  $(div).keydown(handler9);\n" +
                  "}"
       },

--- a/browser/devtools/markupview/test/browser_markupview_events_jquery_1.6.js
+++ b/browser/devtools/markupview/test/browser_markupview_events_jquery_1.6.js
@@ -46,30 +46,34 @@ const TEST_DATA = [
                  "    alert(7);\n" +
                  "  };\n" +
                  "  var handler8 = function divClick2() {\n" +
                  "    alert(8);\n" +
                  "  };\n" +
                  "  var handler9 = function divKeyDown() {\n" +
                  "    alert(9);\n" +
                  "  };\n" +
+                 "  var handler10 = function divDragOut() {\n" +
+                 "    alert(10);\n" +
+                 "  };\n" +
                  "\n" +
                  "  if ($(\"#livediv\").live) {\n" +
                  "    $(\"#livediv\").live(\"dblclick\", handler1);\n" +
                  "    $(\"#livediv\").live(\"dragstart\", handler2);\n" +
                  "  }\n" +
                  "\n" +
                  "  if ($(\"#livediv\").delegate) {\n" +
                  "    $(document).delegate(\"#livediv\", \"dragleave\", handler3);\n" +
                  "    $(document).delegate(\"#livediv\", \"dragend\", handler4);\n" +
                  "  }\n" +
                  "\n" +
                  "  if ($(\"#livediv\").on) {\n" +
                  "    $(document).on(\"drop\", \"#livediv\", handler5);\n" +
                  "    $(document).on(\"dragover\", \"#livediv\", handler6);\n" +
+                 "    $(document).on(\"dragout\", \"#livediv:xxxxx\", handler10);\n" +
                  "  }\n" +
                  "\n" +
                  "  var div = $(\"div\")[0];\n" +
                  "  $(div).click(handler7);\n" +
                  "  $(div).click(handler8);\n" +
                  "  $(div).keydown(handler9);\n" +
                  "}"
       },

--- a/browser/devtools/markupview/test/browser_markupview_events_jquery_1.7.js
+++ b/browser/devtools/markupview/test/browser_markupview_events_jquery_1.7.js
@@ -46,30 +46,34 @@ const TEST_DATA = [
                  "    alert(7);\n" +
                  "  };\n" +
                  "  var handler8 = function divClick2() {\n" +
                  "    alert(8);\n" +
                  "  };\n" +
                  "  var handler9 = function divKeyDown() {\n" +
                  "    alert(9);\n" +
                  "  };\n" +
+                 "  var handler10 = function divDragOut() {\n" +
+                 "    alert(10);\n" +
+                 "  };\n" +
                  "\n" +
                  "  if ($(\"#livediv\").live) {\n" +
                  "    $(\"#livediv\").live(\"dblclick\", handler1);\n" +
                  "    $(\"#livediv\").live(\"dragstart\", handler2);\n" +
                  "  }\n" +
                  "\n" +
                  "  if ($(\"#livediv\").delegate) {\n" +
                  "    $(document).delegate(\"#livediv\", \"dragleave\", handler3);\n" +
                  "    $(document).delegate(\"#livediv\", \"dragend\", handler4);\n" +
                  "  }\n" +
                  "\n" +
                  "  if ($(\"#livediv\").on) {\n" +
                  "    $(document).on(\"drop\", \"#livediv\", handler5);\n" +
                  "    $(document).on(\"dragover\", \"#livediv\", handler6);\n" +
+                 "    $(document).on(\"dragout\", \"#livediv:xxxxx\", handler10);\n" +
                  "  }\n" +
                  "\n" +
                  "  var div = $(\"div\")[0];\n" +
                  "  $(div).click(handler7);\n" +
                  "  $(div).click(handler8);\n" +
                  "  $(div).keydown(handler9);\n" +
                  "}"
       },

--- a/browser/devtools/markupview/test/browser_markupview_events_jquery_2.1.1.js
+++ b/browser/devtools/markupview/test/browser_markupview_events_jquery_2.1.1.js
@@ -46,30 +46,34 @@ const TEST_DATA = [
                  "    alert(7);\n" +
                  "  };\n" +
                  "  var handler8 = function divClick2() {\n" +
                  "    alert(8);\n" +
                  "  };\n" +
                  "  var handler9 = function divKeyDown() {\n" +
                  "    alert(9);\n" +
                  "  };\n" +
+                 "  var handler10 = function divDragOut() {\n" +
+                 "    alert(10);\n" +
+                 "  };\n" +
                  "\n" +
                  "  if ($(\"#livediv\").live) {\n" +
                  "    $(\"#livediv\").live(\"dblclick\", handler1);\n" +
                  "    $(\"#livediv\").live(\"dragstart\", handler2);\n" +
                  "  }\n" +
                  "\n" +
                  "  if ($(\"#livediv\").delegate) {\n" +
                  "    $(document).delegate(\"#livediv\", \"dragleave\", handler3);\n" +
                  "    $(document).delegate(\"#livediv\", \"dragend\", handler4);\n" +
                  "  }\n" +
                  "\n" +
                  "  if ($(\"#livediv\").on) {\n" +
                  "    $(document).on(\"drop\", \"#livediv\", handler5);\n" +
                  "    $(document).on(\"dragover\", \"#livediv\", handler6);\n" +
+                 "    $(document).on(\"dragout\", \"#livediv:xxxxx\", handler10);\n" +
                  "  }\n" +
                  "\n" +
                  "  var div = $(\"div\")[0];\n" +
                  "  $(div).click(handler7);\n" +
                  "  $(div).click(handler8);\n" +
                  "  $(div).keydown(handler9);\n" +
                  "}"
       }

--- a/browser/devtools/markupview/test/doc_markup_events_jquery.html
+++ b/browser/devtools/markupview/test/doc_markup_events_jquery.html
@@ -29,30 +29,32 @@
         var handler2 = function liveDivDragStart() { alert(2); };
         var handler3 = function liveDivDragLeave() { alert(3); };
         var handler4 = function liveDivDragEnd() { alert(4); };
         var handler5 = function liveDivDrop() { alert(5); };
         var handler6 = function liveDivDragOver() { alert(6); };
         var handler7 = function divClick1() { alert(7); };
         var handler8 = function divClick2() { alert(8); };
         var handler9 = function divKeyDown() { alert(9); };
+        var handler10 = function divDragOut() { alert(10); };
 
         if ($("#livediv").live) {
           $("#livediv").live( "dblclick", handler1);
           $("#livediv").live( "dragstart", handler2);
         }
 
         if ($("#livediv").delegate) {
           $(document).delegate( "#livediv", "dragleave", handler3);
           $(document).delegate( "#livediv", "dragend", handler4);
         }
 
         if ($("#livediv").on) {
           $(document).on( "drop", "#livediv", handler5);
           $(document).on( "dragover", "#livediv", handler6);
+          $(document).on( "dragout", "#livediv:xxxxx", handler10);
         }
 
         var div = $("div")[0];
         $(div).click(handler7);
         $(div).click(handler8);
         $(div).keydown(handler9);
       });
     </script>

--- a/toolkit/devtools/event-parsers.js
+++ b/toolkit/devtools/event-parsers.js
@@ -215,17 +215,23 @@ function jQueryLiveGetListeners(node, bo
         if (!selector && event.data) {
           selector = event.data.selector || event.data || event.selector;
         }
 
         if (!selector || !node.ownerDocument) {
           continue;
         }
 
-        let matches = node.matches && node.matches(selector);
+        let matches;
+        try {
+          matches = node.matches && node.matches(selector);
+        } catch(e) {
+          // Invalid selector, do nothing.
+        }
+
         if (boolOnEventFound && matches) {
           return true;
         }
 
         if (!matches) {
           continue;
         }
 

--- a/toolkit/devtools/server/actors/inspector.js
+++ b/toolkit/devtools/server/actors/inspector.js
@@ -295,18 +295,23 @@ var NodeActor = exports.NodeActor = prot
   /**
    * Are there event listeners that are listening on this node? This method
    * uses all parsers registered via event-parsers.js.registerEventParser() to
    * check if there are any event listeners.
    */
   get _hasEventListeners() {
     let parsers = this._eventParsers;
     for (let [,{hasListeners}] of parsers) {
-      if (hasListeners && hasListeners(this.rawNode)) {
-        return true;
+      try {
+        if (hasListeners && hasListeners(this.rawNode)) {
+          return true;
+        }
+      } catch(e) {
+        // An object attached to the node looked like a listener but wasn't...
+        // do nothing.
       }
     }
     return false;
   },
 
   writeAttrs: function() {
     if (!this.rawNode.attributes) {
       return undefined;
@@ -336,28 +341,33 @@ var NodeActor = exports.NodeActor = prot
    *         Node for which we are to get listeners.
    */
   getEventListeners: function(node) {
     let parsers = this._eventParsers;
     let dbg = this.parent().tabActor.makeDebugger();
     let events = [];
 
     for (let [,{getListeners, normalizeHandler}] of parsers) {
-      let eventInfos = getListeners(node);
-
-      if (!eventInfos) {
-        continue;
-      }
-
-      for (let eventInfo of eventInfos) {
-        if (normalizeHandler) {
-          eventInfo.normalizeHandler = normalizeHandler;
+      try {
+        let eventInfos = getListeners(node);
+
+        if (!eventInfos) {
+          continue;
         }
 
-        this.processHandlerForEvent(node, events, dbg, eventInfo);
+        for (let eventInfo of eventInfos) {
+          if (normalizeHandler) {
+            eventInfo.normalizeHandler = normalizeHandler;
+          }
+
+          this.processHandlerForEvent(node, events, dbg, eventInfo);
+        }
+      } catch(e) {
+        // An object attached to the node looked like a listener but wasn't...
+        // do nothing.
       }
     }
 
     return events;
   },
 
   /**
    * Process a handler