My Subject: Thunderbird Performance Issue on New Ubuntu LTS PC Hello, We are experiencing a performance issue with Thunderbird on a new PC running Ubuntu LTS Linux. We have two PCs with Ubuntu installed, one with the last and one with the current LTS: On older, less powerful device where Thunderbird runs significantly better. A new PC with better hardware, more RAM more CPU cores etc where Thunderbird is extremely slow. Both PCs are configured with the same email accounts. We did fully copy profile frm old to new to not lose any mails. However, on the new device, Thunderbird causes full CPU utilization after startup and becomes unresponsive for a considerable amount of time, every time we start. Working with it is almost impossible and painful. Here’s what we’ve tried so far on the new PC: Running Thunderbird in Safe Mode. Reinstalling Thunderbird without using Docker. (apk and bash commands) Unfortunately, neither of these steps resolved the issue. We suspect the problem might be related to the current Ubuntu LTS version. As already told the old computer outperformes the new one abt thunderbird. Has anyone else experienced a similar problem or found a solution? Any help would be greatly appreciated. What or how to test next? Any more detail needed? I might get the hardware specs and mailbox sizes but as said newer computer is slower and mailboxes are the same. Thank you! Michael