torbutton advices using the obsolete TorVM
The external application poppup advices using TorVM which is AFAIK obsolete and unmaintained.
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GitLab is used only for code review, issue tracking and project management. Canonical locations for source code are still https://gitweb.torproject.org/ https://git.torproject.org/ and git-rw.torproject.org.
The external application poppup advices using TorVM which is AFAIK obsolete and unmaintained.