Related, macOS has a similar url schema:
x-man-page://man
> The address wasn’t understood
version 125 isn't new enough for you?
Oh you mean firefox looks uses a protocol handler installed on your system to open an unusual link? Never heard of mailto: irc: magnet:? I think even steam had its own at one point.
It does not work for me.
Addendum from https://mastodon.social/@mofosyne/112385581085525369
Turns out that it's because KHelpCenter in some linux distros hooks to these uris. So typing this uri would autoopen these man entries in KHelpCenter.