Pull Requests are not maintaining file read status

Summary

Pull Requests are not maintaining file read status

Steps to Reproduce

1. create a pull request between 2 branches with at least 2 commits in the PR
2. once the PR is created, go to the Diff tab and click all the files to show as "read"
3. git revert the from branch back to the first commit in the PR
4. force-push the commit to the from branch
5. go back into the PR and look at the Diff tab.

Expected Results

Pull Requests maintain the file read status

Actual Results

Pull Requests are not maintaining file read status

Workaround

No Workaround