“Not my problem” code

I believe you can do this with DAVx5. I have calendars syncing to fossify with it.

I ran Debian Sid on my primary computer for a few years, and it broke hard several times, requiring things like booting into recovery and package dependency untangling to fix. It was years ago, so they might have better safeguards against that now, but there's no way I'd recommend that to a new Linux Desktop user.