Moodle in English
Posts made in Moodle in English
You can't restrict by user without a lot of work, but you can simply remove the icon from the toolbar. Go to Site administration > Plugins > Text editors > Atto HTML editor > Atto toolbar settings (https://yourmoodle.org/admin/settings.php?section=editorsettingsatto) and edit the "Toolbar config" field to replace "links = link, teamsmeeting" with "links = link". See screenshot below.
Also, even if you did manage to write the code, the percentage value presented as feedback will change dramatically over time, particularly during the first few attempts at a quiz, so I'm not sure of the overall value of presenting this number as feedback. Student 1 would always see 0%, student 2 would only see either 0% or 100%, student 3 would see 0%, 50% or 100%, etc.