Server owners, who make their own games with command blocks and datapacks on fabric servers, may want to make a mini-game that shows some player glowing for some other specific player. You can't make that in vanilla Minecraft. You need a mod or a plugin for your server to modify the packets sent to players. That's what this project is about.
There's only one command, that controls everything.
/glow <targets: entities> <displayplayers: players>
targets - entities, that are gonna be glowing.
displayplayers - players, that will see the targets glowing. (command overrides old displayplayers)
Reset glowing for targets with this command.
/glow <targets: entities> *reset
Or reset all glowing overrides with this command.
/glow *reset