I just added two new journals to the list of 馃拵馃搼 #DiamondOpenAccess journals in the small Guide that Opens Science at 馃敆https://guide.opens.science/publishing-open-access.html - @span rupdecat pointed me to the Journal of Open Source Education earlier, and then I also found the International Journal of Open Educational Resources.
Does anybody know any other Diamond OA journals to add?
Or better yet - is there already an overview of Diamond OA journals somewhere?