Created by Claude, will be reviewed by @fregante first.

Part of #10253.

prMergeabilityBoxHeader used the old MergeBoxSectionHeader-module__wrapper class prefix. It now matches the bare wrapper__ class, scoped to the Conflicts section, where it matches a single element. No feature uses this selector at the moment, it's only covered by the selector test.

Test URLs

Any open, mergeable PR you can merge, e.g. https://github.com/refined-github/sandbox/pulls

Checked

Checked against the logged-in DOM of the merge box (the Conflicts section has one wrapper__… div; the Checks section is excluded by the scope). Not tried in a browser.