Using Thunderbird 112.0b7 on Windows 11, with three accounts (1 IMAP, 2 Google Mail) and Unified Folders enabled, the Unified Folders Inbox will only show a few new/unread mails, but not the older mail in the inboxes. When I toggle the "Show only unread messages" quick filter on and off, the other mails appear, but the process is very slow and it insists on scrolling to the oldest mail (>10 years) instead of remaining with the newest or selected item. When new mails arrive, they (and only them) mostly show up in the Unified Inbox, but it's unreliable. E.g. when I was changing some Firefox account settings earlier, the email notification for that only showed up in the account's Inbox, not the Unified Inbox, until I switched back and forth between the two. Overall I quite like this latest Thunderbird beta and it's almost made me switch back to Thunderbird (from Mailbird [no relation] or Betterbird), but this bug(?) has made me miss messages and the general performance, while vastly improved vs the last time I used TB, is still sometimes severely lacking (and lagging).