Just a short note on my very recent experience (Today) with ESET for the first time since I installed is 6 or 7 years ago causing an email issue. Normally I have email scanning disabled as I feel it is mostly more trouble than it is worth, but today no email when I started Thunderbird. Little did I initially think ESET was the cause.
Opened the error console (ctrl_Shift+J) cleared it and tried again. Absolutely nothing in the console, no mail and I noticed nothing since the 1st of December. So this is not a new problem, but one I just noticed.
A bit of googling led me to https://support.eset.com/en/kb7728-unable-to-access-or-receive-emails-in-thunderbird-with-eset-product-installed
By this time I had already entered an exemption for Thunderbird in the protocol scanning, but it did not appear to be working. So I followed the instruction on the article and still it did not appear to be working so like a poor copyist I am I tried the instructions again. This time everything went red as ESET got all excited about disabling the protocol. This went away when I re-enabled it. After that off and on again setting restatement mail just started coming in. Hundreds of them for the past two weeks. Sorry if you are one of those I have been ignoring. But I probably did not have time to reply anyway.
Once I was getting mail I got one advising me that the Thunderbird support forum was inundated with users with very similar issues commencing on the 1st December.