Currently running 102.8.0 on macOS 13.0, but I've had this issue [[https://support.mozilla.org/en-US/questions/1317660|ever since upgrading from TB v68 to version 78.5.1]] ever since upgrading from TB v68 to version 78.5.1 on macOS 10.14.6. The short version is that my "'''From'''" column keeps disappearing. See here: https://www.youtube.com/watch?v=0-NoRw6-ibU This video shows how I right-click the column headers to enable the '''From''' column, and it appears correctly. But then I select any other mailbox, and when I return to the original mailbox, the '''From''' column disappears about 1/10th of a second later. The long version is that it's the same for all my mail folders in all my accounts. No matter how I attempt to change which columns are visible and in what order, they always revert to the same old layout when I click to another mailbox and then return to the one I just edited. Things I've tried that didn't improve anything: # I started up in Safe mode, with all add-ons off. # [http://example.com https://support.mozilla.org/nl/questions/1381677], disabled all add-ons, and reset toolbars and controls. # [http://example.com https://support.mozilla.org/en-US/questions/1386480?page=2] and allowed TB to re-create them # [http://example.com https://support.mozilla.org/en-US/questions/1386480?page=1] and allowed TB to re-create it. # I bought a new computer and imported the old profile. As with the other posters with this same problem, my back end is SmarterMail [Professional Build 8125 (Mar 31, 2022)], and that's not something that's under my control to change right now.