Especially on longer courses (but also in other in-course contexts, given the new Boost’s „hungry” usage of the screen estate) the Participants and Grades nav tabs / links can become invisible / unreachable – the teacher is forced to scroll up the page (thus losing the current screen view) in order to get to those links. Cumbersome and uneconomical.

This change – compared with Moodle 3.11 and its Boost theme’s nav drawer  - is not for the better.

I don’t know how it could be improved using the current Primary / Secondary / Tertiary navigation levels, but improvement is needed here.

This is how handy it feels in Moodle 3.11:

And this is how disorienting and strenuous "secondary" course navigation has become in Moodle 4 :