Hi, I am running Thunderbird 115.10.1 (Flatpak) on Ubuntu 20.04. (no extensions except birdtray) I have 4 email addresses added to my TB, and I like to see all of them together, therefore I am using Unified Folders. When I am accessing Unified Inbox, TB is very slow and basically frozen until it loads this folder (often a pop-up appears that 'TB is not responding'). it takes between 30-60 seconds to load my emails (either on start-up, or clicking on another folder, then going back to Unified Inbox). Every other folders open almost instantly. I have to admit I have a lot of emails in the Unified Inbox (~20K), however the inbox of my main email has 18K, and accessing that folder separately is instant. So any operation, other than opening Unified Inbox, is quite snappy. This issue persists since I upgraded to v115, even when I did an OS reinstall (also tried installing apt (v115.11.0)). I have seen this answer: [https://support.mozilla.org/en-US/questions/1428374#question-reply https://support.mozilla.org/en-US/questions/1428374#question-reply] however, nothing changed by resetting the folder.