Tim Hunt

Knowing the nature of the changes, I don't expect that the Moodle 4.x changes would have a significant impact on performance when a student attempts a quiz. Certainly, these changes have been out in the wild for smoe time, and we have not had many other similar reports. Also, lots of other things have canged in Moodle 4.x which might affect performance.

But, really, with performance issues, it is no good guessing. The only way to work out what the real cause of slowness is, is to measure. If you can do some profiling. That normally reveals what is causing the slowness. Instructions on how to get started here: https://moodledev.io/docs/4.5/guides/profiling

Should there be so many icons? To me, it seems like the design of TinyMCE is to put rarely used actions in the menus, to leave the tool bar small and focussed on the key actions.

However, ti seems that everyone who makes a TinyMCE plugin wants their feature right in your face with its own button. (Perhaps, because that is how Atto worked.)

I said "each user can only have one active quiz attempt at a time"

I did not say "users can only log in with one device at a time" (because that is not true - although people have tried to make login plugins to enforce that, but that is a separate issue).

That is probably the plan, but there has not yet been time to work on it.

You can't customised the nubmers if the section is shuffled.