GitHub: How to update the code diff on an open PR?

Question

I created Branches A,B,C. B has all changes of A, C has all changes of B.

I then created PRs for all of them seperately.

PR1 has: Changes of A PR2 has: Changes of A and B

Then I commited PR1.

What I would expect to happen: PR2 (and 3) would update their code differences. --> PR2 has: Changes of only B (and not A anymore)

PR2 still has all changes of A shown in the log - despite these changes already existing on MAIN, there are shown as code differences.

GitHub already allows changes to an open PR by committing to that branch - but apparently does not update the history in cases like this one.

Is there any like - "update" button to reflect the changes? The shown falsy code differences due to a merge make it harder to review a PR imo

Answer 1

PR should be updated automatically. If that doesn't happen try changing the target branch to something else and changing it back to main.