It works just fine. Remember to put the icon somewhere visible after installing by going to "customize" on Firefox. Signed in without issues.

Would be great if it worked. It didn't.

signup doesnt work

This addon is extremely useful to allow me to track my internet usage with RescueTime. I do not have any customisation issues with the addon and it seems to stay logged in. Hopefully more users will update/post their reviews. Make sure you get the latest Firefox version and keep your addons up-to-date to avoid issues.

The add on is quite good. I didn't encounter the customization issues and the add-on didn't change anything.

The setup was simple and it has become an essential productivity tool for me.