Type of bug

Performance issue or memory leak, Error in console

/ess dump all output

https://essentialsx.net/dump.html?id=c00c3aa66a384ca88d6b83172a2d42cb

Error log (if applicable)

https://pastebin.com/QpuRzkTZ

Bug description

I know that this has been asked a few times already but nothing seems to have helped me so far.

Essentials is constantly spamming "Found UUID xxx for player xxx, but player already has a UUID (yyy). Not replacing UUID in usermap." error at the point which console is basically unreadable.
But the worst part is that it seems to have a very negative effect on the CPU and RAM consumption.

I've tried simply deleting usermap.csv, and everything suggested here : #3956

Thanks by advance for your help !

Note : my server is quite old and has been in 1.12, 1.15 and 1.16 before (amongst others)

Steps to reproduce

Have the server running (no need for players connected or anything)

Expected behaviour

The error should not happen, or not taking that much resources

Actual behaviour

Error spamming the console and consuming a lot of CPU and RAM

Closing the issue, manually deleting UUID duplicates (which were not used) in the world folder seems to have worked (for now)