- Add navigation interceptor script that prevents all iframe navigation
- Intercept link clicks, form submissions, and window.location changes
- Send open-external-url messages to parent window
- Use chrome.tabs.create() in extension context, window.open() fallback
- Fix font-size workaround to use 'initial' instead of hardcoded 16px
- Document Chrome extension font-size bug with Stack Overflow reference
This prevents HTML artifacts from navigating away when users click links,
which would break the sandbox message system. All links now open in new
Chrome tabs instead.
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