Dear maintainer(s),

I noticed that package lilypond-doc-html recommends mozilla-browser,
which is currently not available in unstable. I think that it should
recommend "firefox | www-browser"

Thank you for your time,

PS[0]: I am developing a tool to detect such issues:
https://salsa.debian.org/carlespina/check-relations . Reports are
manually reviewed before submission. If you would prefer not to receive
such reports (for specific packages, all of your maintained packages,
etc.), please let me know. Any other feedback is welcomed as well. No
more bugreports for this missing relation will be sent.

PS[1]: more information available in
https://salsa.debian.org/carlespina/check-relations/-/blob/main/README.md
and
https://salsa.debian.org/carlespina/check-relations/-/blob/main/docs/bug-report-extra-info.md