"not a valid repository name" error

[rnhmjoj]

I'm getting this error while generating a package

fatal: remote error:
github:matrix-org/react-gemini-scrollbar is not a valid repository name

The problem appears to be related to the github URL scheme.
ssbc/patchwork#458 mentions old npm versions as a cause but I have version 3.10 which should support it.

[matthiasbeyer]

I'm running in this issue when trying to package scuttlebut:

fatal: remote error: 
  github:ssbc/scuttlebot is not a valid repository name
  Email support@github.com for help
Error during fetch: Error fetching git://github.com/github:ssbc/scuttlebot.git#391718cf4f47bd0a1c8bafc86c24a86e33be5562 from git: git clone exited with non-zero status code 128