While this describes me pretty well, I have to admit an (optional) conversations...

commoner · on Jan 17, 2018

Try the Thunderbird Conversations add-on:

It resembles the old Gmail interface, and it's open source.

bigbugbag · on Jan 17, 2018

Or don't, as we have seen recently relying on addons to add missing functionalities may not be viable through time.

Thunderbird will soon add support for webextensions, who knows what will happen of the legacy extensions further than short term ?

Tomte · on Jan 17, 2018

And you can't move whole conversations, for example. That's a huge pain point for me.

It seems to be a totally different thing than the regular message list, and only some actions work in Conversation mode.