I am running Thunderbird 128 (any version) on a Surface Pro 9 running Windows 11. After sleep/hibernate or going into energy-saving mode, TB hangs for a period of minutes. Eventually it comes back, but it can take 5-10 minutes. I do not have this problem with TB 115 on the same machine, or TB 128 on other machines (e.g. running Windows 10 or Ubuntu). TB 115 on the same machine can take a few seconds to come back (longer than on my other machines), but that s OK. I have the same expereince whether or not I am troubleshoot mode. I have created a new profile with no add-ons (and less acounts) and I have the same problem. I was wondering if it is something to do with the fact that I have 8000 folders, and somehow TB is hanging while it checks all the folders. That account is a fastmail IMAP connection, but I have experienced similar on a backup Microsoft Exchange account (again an IMAP connection) with similar number of folders. Any help would be appreciated.