This is a simple plugin that returns a random server icon upon refreshing a server list.
Upon server start, it checks for server icons in a server-icons folder in the server's root folder (i.e. where your server jar is). It automatically loads any files that fit the criteria of a server icon:
And that's it! Every time a player refreshes their server list with your server on it, they will get a random icon.
Your existing server-icon.png is not touched in anyway, though it's effectively overwritten.
To add more icons, throw them into the folder, and restart your server. Also works with deleting icons.
This project was originally just a way for my friends and I to see all of the server icons we've made over the years, so the versions available may be lacking. If you want to request this plugin for a different version, feel free to leave an issue on the GitHub. I may also make them myself for the most popular old versions (1.7.10, 1.12.2, etc.)