It would be very useful to have a block appearing in the page of the quiz attempt review, showing whether the student was online or not during the quiz. Maybe he lost connection at some point.

Since there is an automatic autosave (in our case it is set up for every 2 minutes) it couldn't be impossible to implement. Here I read that it is triggered if someone changes a question, but in any case it means that Moodle "listens" for changes in the page, and when there is no connection, a red message of autosave error appears to the person taking the quiz.

The idea is that the time allocated for the quiz could be divided in portions of 5% (20 portions) and if there is a click logged, or a successful connection between the server and the student's computer during the autosave process, the portion would be marked green. While if there is no log for the student (on any page of Moodle), or autosave failure, it will be marked as red. This will give the instructor the ability to check if a student lost connection during the quiz and it will be justified to grant him another opportunity to take the quiz.

Please see my screenshot attached.