Obviously they decided not to focus on that particular feature, yes. Given its importance, seen as a table stakes UI feature by most other email clients, that clearly indicates development is stalled.
You obviously believe that it's important, but maybe the Thunderbird maintainers don't? I have never had any problem with it, and I'm probably not alone.
I read the comments in the bug linked above. It’s funny that some of the rants mention “I’m switching to X” where X isn’t even around anymore today. TB still works after all this time.
