Every panel was visible until Alpine booted — four role="tabpanel" regions at
once for a screen reader, and aria-controls pointing at ids that did not exist
yet. The panel now carries its id, its aria-labelledby and, unless it is the
chosen one, display:none from the server. A slot renders before the component
around it, so the panel reads <x-tabs>'s attributes off the component stack and
repeats its id and initial-tab lines; both files say so.
Plan: docs/plans/material-3-alignment.md, step 14 (navigation N-05).
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Qwx5USif3wFFmxtHg5U1g9
