I have this add-on and tested it before. Regardless of many downvotes, I can’t understand the scoring, when I select the correct answer, it highlighted the other options in “green” color as well, while they should be colored in “red” and when I click a wrong option (of 5 options), it shows 60% correct answers with wrong and correct options highlighted in red. It’s a bit confusing.
Another problem I have with this and asked here is it doesn’t show options until I click the “Sync” button and then options appear!