That’s very interesting - in this new topic a user reported almost the same issue, but I was unable to reproduce that on my 7.5.1 demo.
Can you tell me a bit more about your environment, please? What deployment model (binary, docker, omnibus, etc.) did you use and can you share the output of the command jq .FileSettings /opt/mattermost/config/config.json (if this is the path to your config.json)?