edit 2: Restarting my laptop us causing the issue, not leaving/coming back to the local network!!! Interestingly, it doesn’t ask me to log in once I’m at school (i.e. outside my local network), only when I’m in the local network.
edit: Forgot to mention, this issue only affects the desktop client! When using the web client with my browser, I am still logged in.
I have a nextcloud instance that is local to my network, and I don’t trust my IT skills enough to secure my server in the internet, so it only works when I’m at home (or if I use something like Tailscale). I am content with leaving it that way, since I mostly self-host to back up my files, I’m not using anything like Jellyfin or Navidrome at the moment.
Everything seems to work fine, Nextcloud, Immich, my calendar, etc. all sync fine. However, it seems that Nextcloud doesn’t remember my laptop, and logs me out whenever I leave and come back to the network whenever I restart, meaning I pretty much have to login every day. Why is this? How do I get Nextcloud to remember my laptop?


In that case, something is invalidating the login. Are you sure that it is happening due to leaving your LAN, and not just coinciding with that?
Does restarting the laptop log you out, or temporarily disconnecting from the internet? Could you test by switching to a wifi hotspot on your phone, and switching back, for example?
The client stores your session token in the OS credentials manager (kwallet for linux kde, for example) and the issue can lie there, as well.
Yep, it was restarting my laptop. Oops. I have updated the post. Interestingly enough, the popup doesn’t show when I turn on my laptop outside my local network (e.g. when I’m at school) and only shows up when I’m back home (in my local network), and since I always power off and turn on my laptop at school, I never noticed that restarting was the problem.
Then my first assumption is that the session token is not being correctly stored in kwallet. It can’t restore the session after kwallet is closed.
You can open kwallet manager, and delete the wallet. This will prompt your system to re-create it next time you go to use something that needs it (wifi, nextcloud).
This will allow you to essentially reset the default wallet.
The typical settings for it are “blowfish” encryption with either a blank password (which encrypts nothing, but allows the wallet to always open reliably) or using the same password as your user (which allows the wallet to decrypt automatically upon login).
Another user also commented with useful links, the arch wiki page on kwallet is also potentially useful.
I will try restarting and temporarily disconnect and see if the issue pops up. Probably should have done that before…
It might turn out to be something different - but just in case it does log you out after a system restart (but maybe not after network disconnect) it would probably have something to do with kwallet (the key ring which has your credentials) not unlocking correctly.
If that’s the case this or this might be further pointers to look into.