Is it this one, as in the screenshot?
Mary Cooch (personal account)
Interventi di Mary Cooch (personal account)
Moodle in English -> Glossary -> Change glossary category order to something other than alphabetical -> Change glossary category order to something other than alphabetical
@Shirley -if you look at the Site administration section in the Glossary documentation you linked to, you will see how an admin can enable the browse by category option.
Moodle in English -> User experience (UX) -> Returning learners forgetting My courses tab exists -> Returning learners forgetting My courses tab exists
Would it help to add the Course overview block to the default dashboard (Site admin > Appearance} and reset the dashboard for all users? That said, I like Shirley's suggestion 
Moodle in English -> General help -> How to comment on a Tracker issue -> How to comment on a Tracker issue
Assuming you already have an account, make sure you have "Comments" selected in the Activity section (not "All) If you have already done that and still don't see comments then you can ask for support with the tracker via the Moodle community support form
Moodle in English -> Lounge -> Decrease in activity on some forums -> Decrease in activity on some forums
Your second paragraph, Dominique, is particularly pertinent I feel. The question is does HQ have enough motivation to foster an active and welcoming environment to a forum-based community where people are giving help for free, when they could pay for help instead. And if not HQ, then who in the existing forum-based community?