We have been using JetBrains YouTrack for a few weeks now, but we just today finally got our CTO to set up the GitHub integration; unfortunately, all of our existing issues still don't have any commits listed under the "related changes" tab, even though we have been including the issue ID's in our commit messages.
Is there a way to tell YouTrack to scan through all GitHub commits and add the relations for our existing issues?
YouTrack-GitHub integration is not able to rescan the commits. It only works for new commits by listening to GitHub webhooks invocations. For a workaround please see Setup JetBrains YouTrack to connect to SVN.