This bug has been open for ~14 YEARS. Thunderbird not being actively developed is not exactly a recent development.
Reading through this thread I see tons of great MacOS mail clients, but very few Linux and essentially zero Windows. That's why I still use Thunderbird myself-- nothing better has ever come out.
The reason for the lack of implementation has very little to do with a fault on the side of Thunderbird. It's been blocked on Firefox people accepting the changes in https://bugzilla.mozilla.org/show_bug.cgi?id=441414 (which they finally categorically refused to do a few years ago).
Yeah, it's the usual open-source ego-driven squabbling.
Whatever the reason may be, users were left without this extremely useful and desirable feature for fourteen YEARS. Thunderbird at its core today acts and performs essentially identically to 2003. I've been using it myself since well before that. Development on the mail client hasn't meaningfully progressed since, well, _ever_.
We really hope that Nylas Mail will be your cross-platform email app then. Being build on Electron allows us to support all three major platforms and we are 100% committed to it. Nylas Pro (formerly N1) already supports all three and Nylas Mail should be there in a couple of weeks, if 'e0m is to be trusted. :)
You announced your project with tons of fanfare but no Windows client. I realize MacOS is very popular amongst developers, but Windows has a 91% desktop OS marketshare.
From a broad marketing perspective, you should have waited until the Windows client was available. When you finally release it in a week or a month, will you get another frontpage Hackernews post? Probably not.
https://bugzilla.mozilla.org/show_bug.cgi?id=213945
This bug has been open for ~14 YEARS. Thunderbird not being actively developed is not exactly a recent development.
Reading through this thread I see tons of great MacOS mail clients, but very few Linux and essentially zero Windows. That's why I still use Thunderbird myself-- nothing better has ever come out.