Comment (by Roland Haas):

This is intentional (and should be working, do you observe a failure while checking out the code?). GitHub supports accessing the (git) repositories via subversion. In the ET we use this to only download the (large) tarballs for the current release of the ExternalLibrary and not all tarballs stored in history. See https://help.github.com/en/articles/support-for-subversion-clients for GitHub’s doc. I cannot find a ticket about the change right now, but it was discussed in some of the ET calls so should be in the minutes (somewhere…).

If you stumbled across this because GitHub refused to talk to your cluster’s subversion client, then the reason for the failure is most likely a too old OpenSSL library on your cluster.

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Ticket URL: https://bitbucket.org/einsteintoolkit/tickets/issues/2293/thornlists-entry-for-external-libraries-on