I haven't been able to get IMAP emails through Thunderbird on my gmail and outlook accounts for several days. Thunderbird fails to sync and just shows blank folders or old emails without updating with new ones. I disabled all shields in Avast and the emails started working again. I then checked my family's other PCs and sure enough they all had the same problem and all were fixed by disabling all shields in Avast. Is this some sort of bug and how do I fix it?
Happens on the following systems (with various different IMAP accounts and operating systems)
Operating Systems: Win 10 Home 64bit build 1909 / Win 7 Pro 64 bit
Client: Mozilla Thunderbird 68.8.1 (also happens with the previous version, 68.8.0)
Avast Free: 20.3.2405 (build 20.3.5200.575) (also happens with the version previous to this one)