I just click on notes as always but they open in a new pane, except it’s not a tab and I don’t know which setting this is. If I click on several notes it just opens them all equally split across the screen.
I also restarted the app and it remained. I cannot work like this sadly, don’t know what’s causing this.
Things I have tried
I did try to find a key command, and I can open one of the many opened notes into a new window and then actually close it via CTRL + W or with the mouse, but not as long as they’re not part of a new window.
How did you check the plugins? Often you need to close and reopen the vault to fully unload a plugin after disabling it. The easiest thing to do is turn on Settings > Community Plugins > Restricted Mode and reopen the vault to see if a plugin is the problem.
Another possibility: is your Ctrl (or Cmd) key stuck?