Feedback: /api/web/~/BroadcastChannel - Needs Improvement

## Documentation Feedback

**Path:** /api/web/~/BroadcastChannel
**Helpful:** No ❌

**Feedback:**
> It should tell you on this page that you need to add `--unstable-broadcast-channel` - otherwise you need to hunt down a separate docs page for that. All unstable features should show the required `--unstable-*` flag on their page.

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*This issue was automatically created from the documentation feedback system.*

Start at the documentation page for /api/web/~/BroadcastChannel and locate its source in the docs repository. Confirm how unstable features are identified, then make the page state that --unstable-broadcast-channel is required; the work is done when the page clearly shows this requirement.

Written by the indexing model from the issue text.