Deprecation of the git:// protocol on GitHub

Last year, GitHub announced the deprecation of the unsecured Git protocol due to security reasons. This change will be made permanent on March 15, 2022.

At Read the Docs we found around 900 projects using a Git protocol URL (git:// to clone their projects. To save time for our users, we have migrated those to use the HTTPS cloning URL instead (

But there are other places where projects may be using a Git protocol URL, like in submodules or dependencies. You’ll need to migrate those to use a supported protocol in order for your builds to keep working after March 15, 2022. In most cases, this means changing URLs that start with git:// to start with https:// instead. If you have doubts, please check the documentation of the tools you are using, for example:

If you are trying to clone a repository using the Git protocol, you may see an error like this:

Cloning into 'testing'...
fatal: remote error:
The unauthenticated git protocol on port 9418 is no longer supported.
Please see for more information.

Note that this applies only to repositories hosted on GitHub, repositories using providers that support the Git protocol won’t be affected.

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