I'm using Thunderbird 102.10.0 on Ubuntu. For me it was Edit\Settings, then clicking on 'Config Editor...' On the 'Advanced Preferences' tab, type in 'mailnews.default_view_flags' as noted by Pjotr, above. Change it to '0'. I found this on https:...
I think I've figured out how to do this. I posted on Keep Thunderbird folders set to 'Sort by' 'Unthreaded' Look for the post from 'beagantx'Recap: In your Thunderbird folder (in my case: ~/.thunderbird/zhihbfsb.default-release-1) is a file: xulsto...
