Stuck Apple Mail - how to reset?

i received a message with my Apple Mail that was obviously too "heavy" for my hardware (no malware just too many nested and forwarded mails inside one message - bad luck in a way)

And now Apple Mail freezes each time I start or restart it (after rebooting the complete machine, or/and the program) and shows me the folder "trash" where this particular message that occured the freezing is into.

Is there any chance that I can (re)set the default folder that is shown when opeining mail to inbox e.g. instead of the last folder open ?

How would I do that without putting all settings to blank?

Thanks for your help!

You could perhaps try deleting the saved state files, then on next launch it would return to a default view.
The advantage is that no other settings would be changed - nothing lost.

~/Library/Saved Application State/com.apple.mail.savedState

Because it's an alias, don't delete the folder itself, just the contents.

That would potentially allow you to empty the Trash folder without having to first open it.