So what is wrong with Thunderbird? In my case it has a track record of presenting me with with a regular series of bugs and problems. Also, over the nearly 10 years I have used it, I have seen not a single beneficial feature added. So, from my perspective, some inept programmers tinker with it and cause me trouble.
Not unlike how I used to view Microsoft. Nothing new. Nothing exciting. Nothing going on. No risk. Maintain old crusty things and introduce more new bugs that they fix. Supposedly lots of talent and resources, but nothing ever comes out the end of the pipe. Who would want to work at a place like that?
The latest hassle was that they broke the add-on mechanism, which broke the keyconfig add-on. Never mind that thunderbird ought to have an offical and supported build in mechansim for configuring keyboard shortcuts.
I have heard that the Mozilla foundation is dying. They laid off first 80 employess, and more recently another 250. What could all of these people possibly have been doing? There has never been anything beneficial done from my point of view as an end user, that is for sure. Mozilla has had a checkered history anyway, and frankly in my opinion, they deserve to die and the sooner the better.