The complexity of Moodle upgrades is rarely anything to do with moodle and everything to do with 3rd party plugins.
Exactly!
I'm sorry, I missed an important piece of information in my previous post. The question is solely about the plug-ins, and not a small number of them.
Upgrading the core was simple. In fact, I did it already in a staging server. The staging server is Moodle 4.5 LTS compatible with PHP 8.2 and MariaDB 10.11. Basically I did what Moodle migration says, except that "to test the water" I took only the core 4.1 code to the staging server, and marched the code to 4.5 using Git. Then ran the Moodle upgrade script. All went well except that as expected the plug-ins page now shows 100 plug-ins missing from disk! Otherwise all works, I can navigate everywhere, Debugging raised, other than the resources and activities that came from those missing plug-ins. So no problem, no questions there.
Also note that it is simple to repeat the the core upgrade in the staging server described above. I don't mind repeating it a couple of time to find a good strategy (with you all) for the plug-ins, since other Moodle instances are waiting. ;)
-> So the question is: How would you proceed with the 100 plug-ins? <-
a) Would you take the plug-ins (the 4.1 LTS versions of them) together with the core, means the full code tree? And then what?
Or,
b) would you take only the code as I did, and install them anew? And how, with Git? Through the Moodle font-end?Again keep the number 100 written in front of you! ;)
The plug-in code is only slightly touched in a handful of plug-ins, when they broke in during production and the developers or the tracker issue showed short manual fixes - so called "code hacks".