For some days pamac offered 50 updates for my system and although I did not understand why I let pamac install them yesterday. This broke my system. With help from @ maycne.sonahoz I got the system back to normal. Again pamac reported 50 updates.
Now I am wondering why this happened. It seems this:
Briefly changed branch from Stable to Unstable to update 1 application
After choosing ‘refresh databases’ in pamac the updates were gone / not offered by pamac.
I understand that partial updates are discouraged and unsupported. (The 1 updated application, i.e. Ardour 7.1, did not trigger other updates and ran fine on Stable.)
Why is pamac not triggered by the pacman syncing process to update the update list? (All 50 updates were from Manjaro’s Unstable, none were AUR). Is it possible / advisable to create a pacman hook which triggers pamac to refresh its database?
How would pacman/pamac know that you changed branches?
Changing branches is nothing fancy, it is merely pointing the mirrors to another folder (stable/testing/unstable). Changing branches should not be done willy-nilly, you are responsible for cleaning up.
My point is that in the process of switching branches pamac is left out: pacman cleans up but forgets to inform pamac. pamac then presents updates which should not be installed.
Yes, I recognize being responsible for this, I don’t blame anyone and am thankful for the help on this forum. But it seems to me feasible and clear that pacman informs pamac to refresh its database. pamac fooled me with the list of updates.
I will not make this mistake / oversight twice i.e. forget to manually update the pamac database. My post is also meant to make Manjaro even better than it already is!