Several weeks ago, I developed my own service that uses Google's oauth2 for authentication. It used a popup window method to reach Google's oauth2. It worked for both Chrome and Firefox. Then, I noticed that oauth2 UI has changed a bit and the popup on Firefox is no longer work, yet it still works on Chrome. This happened exactly on 17 Dec 2018. I fixed that by changing the method to reloading the callback in the same tab/window without popup and it's fine on both Chrome and Firefox. Since then, I found more services that use the popup method against Google oauth2 were no longer work on Firefox. Some of them fixed it by moving to reload method.<p>I'm not sure whether the Firefox update or Google's oauth2 update that has caused this.<p>Is there anyone experienced this? If your service uses the oauth2 + popup method, you may check if it still works on Firefox.