Works as I expected. Prevents the user from opening too many tabs, helping with focus/organization.

Con: Value for max number of tabs resets every update.

Please, create option to not show message "You have decided not to open more than $1 tabs."

What would be perfect is the ability of blocking all Firefox, even with other Windows opened, to 4 opened views.

One feature request that would make this extension perfect for me. Automatically delete tabs based on some kind of LRU ordering.I use a similar extension for chrome and it uses a combination of least recently used and number of times selected to determine which to close and it works great.