Yesterday I got an update for my Kubuntu-Linux-System 18.04.3 LTS, and also the package “nextcloud-client” was updated. After that, I was not able any more to log in into the sync-client. It only opens Firefox where I can log in into my installation itself, but the client does not work any more.
Sometimes then it says in browser “Zugriff verboten. Dein Anmelde-Token ist ungültig oder abgelaufen”, but when I edit the link login is possible. Although - the client does not start working.
What can I do?
log into the webif (as the user connecting with nextcloud-client), go to settings -> security and delete the session(s) of the old client (and maybe the old expired ones).
Thank you for your fast answer. I found the sessions under “User → Settings → Security” and deleted lots of sessions there. Unfortunately the problems is not solved by doing that. When I reopen the client, I see “Change to your browser to log in”. The client is not working as a client. It only says “disconnected”, even when I am logged in via browser.