Hi! I need your help! No one I know uses thread grouping in the mail list. Except for one person who asked me for help. I checked, and I have the same problem: Thunderbird 140 ESR doesn't save the expanded or collapsed status of threads. Even changing folders and returning causes all threads to be collapsed or expanded (depending on the last expanded/collapsed all hotkey pressed). A friend claims that everything was saved for him before. I tried resetting the global index, but it didn't help. Please, if you know the setting responsible for this, or know the correct behavior for Thunderbird, let me know.