FrontendHaltBrowser internals·Advanced·Conceptual·1 min read
Can a cross-origin iframe read its parent page's DOM?
Short interview answer
Not by default. The same-origin policy blocks that access unless both frames share the exact same origin, or they opt into a narrower communication channel such as postMessage.
Key takeaway
Explain the underlying mental model clearly, then support it with a concrete example and its trade-offs.