[Feature request] Make Pluto built-in package manager support github links (if it isn't supported yet)

[Alseidon]

I love using Pluto, which makes everything flow smoothly, but I have to use a package which isn't in the general registry (yet?), meaning I have to use Pkg.add(url="https://github.com/user/package.jl"). Is there a way to reproduce this behaviour without disabling the built-in package manager? If not, could this be "easily" supported?

[disberd]

There is an open draft PR by me #2245 which has been stale for a long time.
I still didn't find the time to update it and work on it again, but unfortunately it is currently not possible before this PR (or something else similar is implemented).

[Alseidon]

Thank you for your answer!