Thank you for the 5 stars. There is another developer maintaining the that other firefox port. They did their port well before we made thid official firefox port :) But yeah if both are instead you probably get some race conditions causing issues.

If you'd like to support development, you can donate to me here: https://github.com/sponsors/namakeingo
or sponsor the creator, @zpix1, here: https://zpix1.github.io/donate/