I have searched around but it's all about people complaining the bug. Many posts say that you should check all your extensions.

However, this is something I encountered when I am developing an extension.

Here is how it happens:

I have a listener on background.js:

chrome.extension.onMessage.addListener(function(request, sender, sendResponse) {
  console.log('get:', request);
  if (request.hasOwnProperty('opt')) {
    trackPage('opt/' + request.opt);
  }
  return Promise.resolve("");
});

And here is the trigger in my option page:

track('something');
function track(msg){
  chrome.runtime.sendMessage({opt: msg}, function(response) {
    console.log(response);
  });
}

The error occurs when the track function is fired.

How can I fix the error totally?

I have searched around but it's all about people complaining the bug. Many posts say that you should check all your extensions.

However, this is something I encountered when I am developing an extension.

Here is how it happens:

I have a listener on background.js:

chrome.extension.onMessage.addListener(function(request, sender, sendResponse) {
  console.log('get:', request);
  if (request.hasOwnProperty('opt')) {
    trackPage('opt/' + request.opt);
  }
  return Promise.resolve("");
});

And here is the trigger in my option page:

track('something');
function track(msg){
  chrome.runtime.sendMessage({opt: msg}, function(response) {
    console.log(response);
  });
}

The error occurs when the track function is fired.

How can I fix the error totally?

• javascript
• google-chrome-extension

• Chrome extensions API doesn't support Promises. Either use the API the way it's shown in the documentation or switch to the modern way with Mozilla's WebExtension polyfill. – woxxom Commented Mar 19, 2019 at 4:53
• Would you please share more information about the two ways? Thanks! – darkrose1977 Commented Mar 19, 2019 at 5:35
• I thought you would google up the keywords I gave. The documentation. The polyfill. – woxxom Commented Mar 19, 2019 at 5:38
• Did you find a fix for this? – Patrick Clancey Commented Oct 18, 2019 at 15:55
• not yet. just give up – darkrose1977 Commented Oct 22, 2019 at 4:14

6 Answers 6

You can't return a Promise to make the function async, you have to return true. So change this:

return Promise.resolve("");

To this:

Promise.resolve("").then(result => sendResponse(result));
return true;

I'm not sure why all the "it's Chrome extensions" responses are down-graded. I turned off all extensions; problem gone. Tried different browsers (even Microsoft); no problem. Back to Chrome and turned one extension back on; problem returned. Tried with a simple web page: <?php ; (yes, nothing) problem persists.

So, fuggedaboudit. Or, quoting Bill Murray in "Meatballs," "It just doesn't matter!"

In my case I just replaced the old chrome apis which were inside a Promise with updated ones:

Old:

  sendMessageToTab: (tabId, msg) => {
    return new Promise(resolve => global.chrome.tabs.sendMessage(tabId, msg, resolve));
  },

The updated ones:

sendMessageToTab: (tabId, msg) => global.chrome.tabs.sendMessage(tabId, msg)

If you see this error on other websites too then don't be bothered because it's not generated by your app, probably some Chrome Extension.

I disabled Tampermonkey Chrome extension and the error disappeared.

check extentions chrome, update or remove or deactive