The original plugin page is https://www.spigotmc.org/resources/staff-core.82324/ (in the event the plugin/resource ever gets removed, here is an archive.org backup/snapshot https://web.archive.org/web/20220810035544/https://www.spigotmc.org/resources/staff-core.82324/)

I contacted Barrar3Port the original author and even though he has not stated on the plugin page that is it inactive/unmaintained by him, when I contacted him in the LyMarket discord (He has dms disabled and his own discord has no channels where normal members can talk so that was the only one I could reach him), he said he wasn't working on it anymore (unfortunately when I went to rejoin the LyMarket discord server for proof before posting this resource, it appears it have been deleted (The invite link is invalid) so you'll have to take my word for it)

This plugin has a few improvements from the base design and hopefully more to come, I'd say the most important are:
- Replacement of all code reliant on his website api which was at staffcore.glitch.me (Don't ask me why this was the case but now it is either handled completely in code or calls the actual mojang api for things like grabbing heads ( https://github.com/JordanPlayz158/StaffCore/commit/124a2c1f49d386f12694202721701f9a42a7faa3) and checking the latest version which spiget has a nice api for and is tied to spigot which has a way lower chance of going down ( https://github.com/JordanPlayz158/StaffCore/commit/a4aef29e67c6b62afc4ead6d85fd4dc219f88433))
- Removal of Barrar3Port's Telemetry, it doesn't work anymore as his glitch api is down but either way, it's bloat and personally, I don't think that kind of bloat should be in the plugin (especially as the disable telemetry boolean in the stats.yml file was never used in code so you couldn't even disable it (The reason I kept bStats is because it is a known metrics system and can actually be disabled with a boolean), you'd just get a placebo effect ( https://github.com/JordanPlayz158/StaffCore/commit/e163bb0f538e21ca36bcaa7b5a69ec192fe77db0))
- Removal of the web linking system, for one, his glitch.me site is down so it wouldn't work anymore and tbh, sounds like a really bad idea for security to send your db to and manage staff-related things like infractions through an external panel (that can go down at any time and likely has a higher risk of being compromised)
- Some things devs may like is the fixing and conforming of the java package and class naming conventions ( https://github.com/JordanPlayz158/StaffCore/commit/1b8520718bcba5dcab53ae2a4461cbd1ec96a873) although there still are some PascalCase variables instead of the correct camelCase as this requires manual intervention to my knowledge so it will take some time

View the plugin page at the top of the description for all the features (other than the ones I said I removed or changed above)

Note: The API-Version disclosed in the plugin.yml is 1.13 BUT the dependency in the pom.xml is for the 1.17 spigot api so unsure of which is more accurate