The green check marks on the Discourse upgrade page indicate that a plugin is an official plugin maintained by Discourse, as explained by itsbhanusharma. However, users found the meaning of these green checks unclear, with some suggesting the addition of a tooltip for better understanding. zogstrip initially mentioned adding a tooltip but later realized it already existed. The tooltip was further improved with a title by zogstrip.
Some users, including pfaffman, suggested replacing the green check with the Discourse logo for better clarity. Although Font Awesome does offer a Discourse icon, as pointed out by david, updating the icons would require changes, as mentioned by Falco.
Additionally, pfaffman raised a concern about the potential for confusion if someone forks an official plugin or creates a plugin with the same name, making it appear as an official plugin. zogstrip acknowledged this possibility but stated that the green check is just an indicator and that people could manipulate the official? method to return true.
I’ve noticed in my own Discourse installation that some weeks ago green checkmarks started to appear on the left of most of the entries on the upgrade page: