Re-normalizing a repository After you’ve set the core.autocrlf option and committed a .gitattributes file, you may find that git wants to commit files that you’ve not modified. This is because git wants to normalize the line endings for you. The best way to do this is wipe out your working tree (all the files except the .git directory) and then restore them. Make sure you’ve committed any work before you do this, or it will be lost.
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"Only do this on commits that haven’t been pushed an external repository. If others have based work off of the commits that you’re going to delete, plenty of conflicts can occur. Just don’t rewrite your history if it’s been shared with others."