The sidebar system prompt pushes the agent to run \`\$B snapshot\` as its
primary read path, but snapshot was NOT in PAGE_CONTENT_COMMANDS, so its
ARIA-name output flowed to Claude unwrapped. A malicious page's
aria-label attributes became direct agent input without the trust
boundary markers that every other read path gets.
Adding 'snapshot' to the set runs the output through
wrapUntrustedContent() like text/html/links/forms already do.
Caught by codex adversarial review.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Garry Tan
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