I’m not having any issues using it with one hand so far. Not even sure what is very different about the UI beyond a different icon set and the account switcher being fewer taps to get to. I’m curious what about the new app makes it hard for you? Maybe there’s something highly annoying that I haven’t run across yet.
Ah yeah that sounds really frustrating. I’m sure you’ve tried this already, but does Lineage have support for the one-handed mode gesture? I’ve had that come in handy (no pun intended) now and then.
I read somewhere that the Thunderbird team was working on fixes for the new drawer UI, here’s hoping they take better accessibility in mind!