Failure to install via package via readme instructions (bad branch name?)

[idbrii]

Added to manifest.json like so:

    "com.sitterheim.unityresolutiondialog": "https://github.com/sitterheim/UnityResolutionDialog.git#release/stable",

Unity gives an error:

An error occurred while resolving packages:

Project has invalid dependencies:
com.sitterheim.unityresolutiondialog: [https://github.com/sitterheim/UnityResolutionDialog.git#release/stable] does not point to a valid package repository. No package manifest was found. Verify the repository URL and make sure the package is located in the root folder of the repository.

A re-import of the project may be required to fix the issue or a manual modification of C:/code/project/Packages/manifest.json file.

Reimport All results in the same error.

Workaround

Track master instead of the stable branch:

    "com.sitterheim.unityresolutiondialog": "https://github.com/sitterheim/UnityResolutionDialog.git",

Since the branches are currently identical, I assume the issue is the / in the branch name. Branches definitely work since dbrizov/NaughtyAttributes uses a upm branch and I use this in unity-vimeditor with a latest-release branch.

Unity 2019.4.16 on Win10 x64.