Monthly push from internal trunk seems to have broken open pull requests

[henrikingo-oracle]

MySQL version / commit

trunk

Steps to reproduce

The symptoms are visible on PRs that were opened before the push. It seems some commits were lost or reordered, and as a result they show up as part of the PR instead, as long as the PR is not rebased rather is based on yesterday's trunk.

Expected vs actual result

Expected: Only files I edited and committed are shown in the PR diff view

Actual: PR suddenly has additional commits, which maybe older than the PR itself. Also merge conflicts are now on the PR.

Platform / compiler

No response