--- a/testing/mochitest/BrowserTestUtils/ContentTask.jsm
+++ b/testing/mochitest/BrowserTestUtils/ContentTask.jsm
@@ -112,15 +112,17 @@ var ContentMessageListener = {
       } else {
         deferred.resolve(aMessage.data.result);
       }
     } else if (aMessage.name == "content-task:test-result") {
       let data = aMessage.data;
       ContentTask._testScope.ok(data.condition, data.name, null, data.stack);
     } else if (aMessage.name == "content-task:test-info") {
       ContentTask._testScope.info(aMessage.data.name);
+    } else if (aMessage.name == "content-task:test-todo") {
+      ContentTask._testScope.todo(aMessage.data.expr, aMessage.data.name);
     }
   },
 };
 
 Services.mm.addMessageListener("content-task:complete", ContentMessageListener);
 Services.mm.addMessageListener("content-task:test-result", ContentMessageListener);
 Services.mm.addMessageListener("content-task:test-info", ContentMessageListener);

--- a/testing/mochitest/BrowserTestUtils/content/content-task.js
+++ b/testing/mochitest/BrowserTestUtils/content/content-task.js
@@ -30,16 +30,20 @@ addMessageListener("content-task:spawn",
       stack: getStack(err ? err.stack : stack)
     });
   });
 
   var ok = Assert.ok.bind(Assert);
   var is = Assert.equal.bind(Assert);
   var isnot = Assert.notEqual.bind(Assert);
 
+  function todo(expr, name) {
+    sendAsyncMessage("content-task:test-todo", {id, expr, name});
+  }
+
   function info(name) {
     sendAsyncMessage("content-task:test-info", {id, name});
   }
 
   try {
     let runnablestr = `
       (() => {
         return (${source});