
Random emails are disappearing in one inbox on one device only
In the past week or so I have noticed that some emails disappear from one inbox on my Windows 10 PC. I have three Thunderbird accounts (call them A, B, and C), and the emails only disappear from box A. It seems completely random, and furthermore they only disappear on my own PC. My husband has an identical set-up on his Windows 10 PC, which also includes the boxes A, B, and C, and the messages do NOT disappear there. I can also see them on my iPhone and two iPads, and they do not disappear from those. I have tried forwarding them to myself from my phone, and while most of them did show up in the A inbox on my PC, I have noticed that some of them have now disappeared again.
This is incredibly frustrating, because I do most of my work at my PC. I thought I needed an update, but TB says I am up to date (128.8.0esr (32-bit)). It can't be anything to do with the server, because it is so specific: one inbox on one PC only. There doesn't seem to be any special pattern--some have attachments, some don't.
Many thanks for any suggestions!