It created many duplications for the opened tabs and broked the logged in pages.

I've disabled, uninstalled it, restarted Firefox, but the address bar and tabs still show that the addon is working.

This add on indeed does its job, but it also breaks (some) websites login processes and for some others damages the overall look and display.

Must have addon when using Google services.

Great product, very helpful and intuitive.

Pretty fantastic.

The only gripe I have is that it will break "Login with Google"-style auth if (but seemingly only if) the site opens a pop-up window for Google's OAuth flow. I think this is because it instantiates a new window to replace it and breaks the link between child and parent window (i.e. the `window.open` JS call on parent page).

Not sure they can do much about that so it ends up being a pretty serious caveat in some cases.

I mitigate this by taking the opportunity to login in a different browser and change my authentication method away from Google.

Farewell google!

I wrote a pull request for this add-on. The source code looks safe to me. The maintainers were friendly and helpful. The add-on itself is very useful and configurable.