The behavioural check for the detailed-rail rename clamp (#534, #526) lives in test/inline-rename.test.ts, a browser suite the CI gate does not run. This pins the cascade from styles.css itself, from computed selector specificity and source order, so a later clamp rule cannot silently out-rank the shared unclamp again. Mutation-checked: deleting the detailed-rail twin fails exactly that case.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>