Step 1:
Azure TFVC Repo -> Azure Git Repo
https://docs.microsoft.com/en-us/azure/devops/learn/git/migrate-from-tfvc-to-git
Step 2:
Azure Git Repo -> GitHub
- Enable alternate authentication credentials and specify user name and password
- Go to a repository of your project (Code=>Files), click Clone to get the HTTPS URL.
- Go to Github=>Import repository
- Type repository URL (step 2)
- Type alternate authentication credentials (step 1) when it asks for credential
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https://developercommunity.visualstudio.com/content/problem/449985/export-devops-repos-to-github.html