Interesting, that means git is violating the URI spec. Quoting RFC 3986:
> [...] schemes are case-insensitive [...] An implementation should accept uppercase letters as equivalent to lowercase in scheme names (e.g., allow "HTTP" as well as "http") [...]
> [...] schemes are case-insensitive [...] An implementation should accept uppercase letters as equivalent to lowercase in scheme names (e.g., allow "HTTP" as well as "http") [...]
https://datatracker.ietf.org/doc/html/rfc3986#section-3.1