Why Facebook API responses have `for (;;);` at the start of the JSON

Question

An example API response:`for (;;);{"payload":{"keys":[]}}`

ten13 · Accepted Answer

I suspect it&rsquo;s designed to mitigate XSSI, Angular&rsquo;s got one of the easiest to digest explanations[1].1. https://angular.io/guide/security#cross-site-script-inclusio...

Why Facebook API responses have `for (;;);` at the start of the JSON

An example API response:
`for (;;);{"payload":{"keys":[]}}`

I suspect it’s designed to mitigate XSSI, Angular’s got one of the easiest to digest explanations[1].
1. https://angular.io/guide/security#cross-site-script-inclusio...