Wait, what? I use the class functionality all the time. What have you replaced it with?
In particular, I encounter these particular user stories regularly:
* I want most of my folders to be hidden in most menus and contexts most of the time.
* I need to be able to easily unhide the hidden folders when I need to access one that I rarely use.
If you've removed the functionality that enables these without replacing it with something comparable, that's a huge functional regression.

thanks for deactivating the aggressive telemetry - it is always better to ask the users! IMHO this belongs also to the "Free" in FOSS projects - the freedom to choose if I want to share some data with you - no matter what my reasons are.
Thanks

Will my beta version automatically update to the full release version through the updates from Google Play Store, or will I have to install the full release version, and remove the beta from my devices?

will upgrading from K9 be something that eventually happens with regular updates, or is it to be a manual switch over at some point?

import from K9mail stable fails with "can't read the settings file" roughly translated

It looks nice, but I'm only able to use it once it supports configuring accounts to only fetch mails in a defined time range (i.e. during office hours). Do you plan to implement this, by chance?

I updated from 8.0b1 to 8.0b2 without any problem.
I never used the "folder class system" so for me it cool that you removed this feature.

WO telemetry and from F-Droid i'd like to participate.
☺️
#ThunderbirdForAndroid #Thunderbird

And all iOS users continue to sit in the corner crying and hoping for an app.