The add-on has a huge bug. You cannot go back to previous pages on Wikipedia.

Explanation: Open one article and click a link to another article. Now if you press back multiple times, Firefox will open article 1, then article 2, then article 1, then article 2 and continue infinitely.

Problem 1: It's not possible to go back to the page that was opened before article 1.

Problem 2: If there was no page open before article 1, Firefox should stop going back and disable the back button, but instead it keeps cycling between both articles infinitely.

Reason: Firefox doesn't go back in your tab's history when you press the back button. It opens the previous page and adds it to the history again and again.

If it wasn't for that, it's a great extension.