This add-on makes Firefox usable for me, it is indespensible.

The Developer not wanting to add another form of authentication method for 2FA seems a bit over the top, admittedly: that's a recommended minimum authentication practice for any site (i.e., not a cure-all), will certainly become ubiquitous relatively soon and is certainly not just for use with financial institutions. Perhaps you will reconsider your latest position to discontinue support due to 2FA implementation for Developers.

Coming from Tabs Menu where I could scroll through over a hundred tabs easily from a menu-based list, the enforced move to WebExtensions really worried me. This add-on gives me a button I can place in about the same position and provides both a listing of all tabs, plus a quick way to search, close, etc. - more than I've had before! Very thankful for this work and while I realize the Mozilla WebExtension APIs are rather limiting, if you can see a way to perhaps offer a larger size for the pulldown list dimensions and allow for increased spacing above and below list items, that would be ideal. Otherwise, it's fast enough and keeps me productive, great work.

Update 12/2019: The Developer was HIGHLY responsive and updated the add-on to overcome a regression. Back to five stars!