VerusAutenticus
Those are all the previous files before you switched to the file system. Even though you installed the plugin it will not automatically migrate all the files for you. For this you must run a CLI command to manually migrate the existing files in batches. You can search older threads as this has been explained many times with steps and everything.
Keep in mind this only applies to files uploaded before you changed your system settings to start using the file system. All new files will start storing on the file system but the previous, existing files need to be migrated.
Also your osTicket version is old and no longer supported. It’s highly encouraged that you upgrade to the latest ASAP.
Cheers.