Check settings>appearance and see if the features there address your concern

Check settings>appearance and see if the features there address your concern

It doesn't seem to make any difference what I change there.

Joan, have you tried View>threads>expand all threads?

Chester, those settings are for folders you create after making this change, not for existing folders.

Settings > Appearance > Sorting and threading does have options for applying settings to existing folders, but they do not include a setting for expanding all threads by default.

"Expand all threads" operates only on the selected folder.

Joan, I do not know a way to do what you want. I could not find an add-on that would do it.

The problem I have is that "expand all" works fine but is not being applied to newly generated threads that is when a second email message arrives which creates the thread - this newly created thread in not being expanded despite "expand all" option used on the folder; going out the folder and back in again solves the expansion but it is not a vaiable solution Can you please have a look at it?

The options for expanding and collapsing all threads seem to be commands, not a settings. They operate only on current threads in the selected folder. Thunderbird does not remember those commands either to apply them to new threads or to retain the view of one folder after the user has selected a different folder.

As far as I know, the only thing that a user can do is keep using the keyboard shortcut (*).

This is no an option (to use * all the time). In general the main issue is when new message arrives and it is being hidden within collapsed thread. How to make new message appear unconditionally?

BTW It works a like a seeting as when you go out of a folder and come back to it - then the thread is expanded!

PS. Fortunately there is a bird that does it better...