window.open() doesn't transfer the user gesture to the new tab, so autoplay
is blocked. Previously play().catch(()=>{}) swallowed the error silently while
setting playing=true, leaving the UI in a broken state.
Now: if play() rejects, reset state and show "Click Play to start". The user's
click on the Play button IS a user gesture, so it succeeds on the second attempt.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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