Unread message marked as read by its own
Hello,
Yesterday (28-09-2022), Thunderbird set an unread message as read by its own without any manual intervention. I haven't opened the email from any other device and I am the only one using my account. I also checked for security breach in my account. I haven't also accidentally pressed something (like keyboard shortcut 'M' for marking message read/unread).
Could this be some kind of bug in Thunderbird?
Any other users experiencing this?
I am running Thunderbird 91.11.0 (64-bit) under Ubuntu 20.04 and my email provider is GMail connected through IMAP.
Thank you in advance!