--- a/testing/mochitest/BrowserTestUtils/ContentTask.jsm
+++ b/testing/mochitest/BrowserTestUtils/ContentTask.jsm
@@ -113,16 +113,19 @@ var ContentMessageListener = {
       }
     } 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);
+    } else if (aMessage.name == "content-task:test-todo_is") {
+      ContentTask._testScope.todo_is(aMessage.data.a, aMessage.data.b, 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);
 Services.mm.addMessageListener("content-task:test-todo", ContentMessageListener);
+Services.mm.addMessageListener("content-task:test-todo_is", ContentMessageListener);

--- a/testing/mochitest/BrowserTestUtils/content/content-task.js
+++ b/testing/mochitest/BrowserTestUtils/content/content-task.js
@@ -35,16 +35,20 @@ addMessageListener("content-task:spawn",
   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 todo_is(a, b, name) {
+    sendAsyncMessage("content-task:test-todo_is", {id, a, b, name});
+  }
+
   function info(name) {
     sendAsyncMessage("content-task:test-info", {id, name});
   }
   /* eslint-enable no-unused-vars */
 
   try {
     let runnablestr = `
       (() => {