Non-root user that (suddenly) has elevated privileges in a specific command (only). [Have I been hacked?]

Title. Long,short story: creating or editing files with nano as my non-root user gives (the file) elevated privileges, like I have ran it w/ sudo or as root. And the (only) “security hole” that I can think of is a nextdns docker container running as root. That aside, its very “overkill” security-wise (cap_drop=ALL,...