14th of 20 Questions.
What is SharedArrayBuffer and Atomics? How do they enable true shared memory between the main thread and workers? What security headers are required to use them?
SharedArrayBuffer allows multiple threads to access the same memory; Atomics provides atomic operations to prevent race conditions. Required headers: Cross-Origin-Opener-Policy: same-origin and Cross-Origin-Embedder-Policy: require-corp.
SharedArrayBuffer is a transferable object that remains accessible after transfer, enabling true shared memory. Atomics methods (add, sub, compareExchange, wait, notify) allow safe concurrent access. Due to Spectre vulnerabilities, these features require explicit COOP/COEP headers.