Cheat Sheet
| Question | Core Idea | Senior Signal |
|---|---|---|
| Q266 | Web Crypto | Use standard primitives and focus on the key model; do not invent crypto or store keys casually. |
| Q267 | Realtime | Authorize channels, validate messages, reconnect with backoff, and show stale or disconnected UI states. |
| Q268 | Files | Validate server-side, store safely, scan when needed, authorize downloads, and set safe content headers. |
| Q269-Q270 | Isolation and dependencies | Roll out COOP/COEP/CORP carefully and treat every dependency as a trust decision. |