Since we are in the fediverse, I think it would be convenient to have a fediverse-wide resolvable fediverse URI scheme, that would look like so:
fediverse://
edit: Found a relevant FEP: https://codeberg.org/fediverse/fep/src/branch/main/fep/07d7/fep-07d7.md
To what end?
You wouldn’t need browser extensions to open links on your instance
App maintainers wouldn’t need to maintain lists of instances to correctly signal “I can open this” to the OS
So if your Mastodon instance just sprung up, you can just give someone a link like fediverse://masto.darkthough.ts/post/1337
and it will auto-open using the app and instance account of their choosing.