In Thunderbird, when using a 3-vertical panel layout, the columns get squished (especially long subject lines). It's not a big thing, but I would gladly trade half the vertical space for the ability to fit a couple more fields, like tags and size.
Has it stalled, though? Perhaps they don't see it as a worthwhile feature to focus on. I'm OK with that, even though I'd love to see it implemented. Firefox, OTOH, finally resolved a much more trivial issue 17 years after it was first reported (https://bugzilla.mozilla.org/show_bug.cgi?id=92737) and I'd hardly call that project stalled.
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.
Unrelated to thunderbird, more like how mozilla development works or does not. A new of bugs have been sitting for over 10 years, though they're usually silently closed after a while until someone notices and reopens them.
It could even be something said about other projects who also have bugs sitting for years.
