SysTray-X: A system tray extension for Thunderbird. Needs both the addon AND the companion app installed to work. Will not work with TB flatpaks or snaps.
Err:40 https://download.opensuse.org/repositories/home:/Ximi1970:/Mozilla:/Add-ons/xUbuntu_20.04 ./ Release
Certificate verification failed: The certificate is NOT trusted. The received OCSP status response is invalid. Could not handshake: Error in the certificate verification. [IP: 195.135.221.134 443]
Reading package lists... Done
E: The repository 'https://download.opensuse.org/repositories/home:/Ximi1970:/Mozilla:/Add-ons/xUbuntu_20.04 ./ Release' no longer has a Release file.
Since today the following error message is shown: