Running a self-hosted instance of Joplin Server v2.4.8 on Ubuntu Server 20.04.
Running the Joplin Server behind HAProxy. I can access the Server web UI with SSL termination provided by HAProxy/Let's Encrypt. The certificate is valid and doesn't expire until 6 December 2021.
The syncing was working yesterday for a bit after the initial setup. But later on, starting failing with the following error:
Last error: FetchError: request to https://joplin.domain.com/api/sessions failed, reason: certificate has expired
Interestingly, the syncing completes without error on my iOS device.
It's just the desktop app that seems to have started giving me this error. The same error occurs on the macOS, Windows, and Linux desktop apps.