I have a number of gmail accounts. One of them is of the form xxx@gmail.com. The others use a different domain that is a Google Drive account. They have the form xxx.@ucwc-pa.org. Since updating 68.4.1 Mac 64 bit the xxx.@ucwc-pa.org ones fail with "Failure with connecting to server imap.gmail.com". I've tried restarting Thunderbird in safe mode which did not help. I tried rebooting the Mac to safe mode and that did not help. I tried deleting and recreating one of the accounts that fails and that failed. I can use a browser to get emil from each of the accounts that fail using Googles gmail.com web page.