Draft: Bug 40783: Add a few additional documentation comments after pref review

For #40783 (closed) we did a preference review.

We already merged the changes, however some items were marked as "okayish, but some more investigation would be better".

So, I have already opened the issues for investigations, but a few items were already okay, I just needed to dig a little bit further.

Therefore, with this commit, I'm adding more references, for future ourselves.