Re-wrote git history with bfg but not reflected in earlier commits

问题

A huge folder in my repository has filled up my LFS. As instructed here, I wish to remove the folder from the remote repository and then re-write history to drop it from all previous commits. That should free up lots of space in my LFS, but is not. What am I missing?

Say the repository is repo and the folder in question is repo/unwantedFolder.

I did the following steps:

1. Removed the unwantedFolder and re-committed:

   $ git rm -r --cached unwantedFolder/
   $ git commit -a -m 'Drops folder'
   $ git push origin
   

2. Mirror-cloned the repo:

   $ git clone --mirror https://github.com/emagar/repo.git
   

3. Re-wrote history:

   $ java -jar bfg.jar --delete-folders unwantedFolder repo.git/
   

4. Moved into the manipulated cloned repo: $ cd repo.git/

5. Used the git gc command:

   $ git reflog expire --expire=now --all && git gc --prune=now --aggressive
   

6. Pushed the clean repository: $ git push origin
7. Moved back to the original repository: $ cd repo/
8. Pulled from github: $ git pull origin master

While all seemed to work well, when I inspect old commits in github, the unwantedFolder/ still appears there!

What am I missing?

来源：https://stackoverflow.com/questions/49185076/re-wrote-git-history-with-bfg-but-not-reflected-in-earlier-commits