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.

lose tabs at startup

Tremendously helpful, assists in keeping me focused on a few things and not hundreds of things

I love you so much, this was the last piece of the puzzle stopping me from fully switching from Chromium. I needed this addon because my browsing habits (500+ tabs open) drive me crazy. Thank you!
Edit: A clickable popup window accessible from the addons bar would be great for quick changing of maximum tabs, but I still love you nonetheless :)

Wonderful. One of the best addons for productivity and deep work. Nice to see its resurrection for ff57.

Good replacement for legacy "Max Tabs" add-on. Helps with self-control so I won't open more than 15 tabs.