The encoding can be set when doing something like running micro -encoding utf-16 file.txt or entering setlocal encoding utf-16 and reopen in micro, but BOM is read as a character that can be edited so I think it has to be detected.

I have not used Go much before and I do not know if there are other encodings with BOM that are used a lot, but I was only able to find 1 package where BOM and encoding can be detected:
https://pkg.go.dev/github.com/dimchansky/utfbom

I think I can try adding support with detecting BOM using the package and making a pull request if detecting encodings in the list of Encoding values in the page only would be fine.