This was fixed by changing the support version of the TLS protocol.
The default has changed to TLS version 3.
In Linux I go to:
Scroll all the way to the bottom
Config Editor button
I accept the risk
search for security.tls.version.min
change default to what ever your server supports
I used the following to check what the server ...
Proof of Concept: userChromeJS addon + custom user script
To answer my own question: I managed to pull of this hack which deselects the current selection before the user continues typing.
If someone knows how to turn this into a real Thunderbird MailExtension, feel free to update this answer or start your own!
Install the experimental Thunderbird-...
This is not a bug but by design.
The logic is to download all headers, so all emails will be visible.
This way, when you attempt to read an older email, then TB can download the
body and attachments for you.
The logic on which is based this behavior is extremely convoluted, and as usual
in such over-complex cases, not very user-friendly and not at all common-...
When connected to an IMAP mail server, Thunderbird uses the IDLE command to subscribe to change notifications. Using it will cause the server to start sending notifications every time the current folder's contents change in any way.
Although IMAP is primarily request-response, it does also allow the server to produce various "untagged" messages at ...
IMAP synchronization is always a request-response meganism, exchange however is not.
Exchange can be a request-response meganism, but it can also be a "notify me upon arrival" aka push meganism.
Since gmail uses exchange email can be synched the moment something changes if setup correctly.
Once thunderbird knows the serverside has changed, it ...