Change Details

Since T78449 `generateRandomSessionId` tries to use `crypto.getRandomValues()`, but it tests only the existence of `window.crypto`. At least in Firefox `window.crypto` exists longer (as [[https://developer.mozilla.org/en-US/docs/Archive/Mozilla/JavaScript_crypto|non-standard implementation]], at least since FF16) than `crypto.getRandomValues()` (starting with FF21). The implementation for `generateRandomSessionId` should check not only `window.crypto`, but also `crypto.getRandomValues` before calling it to avoid this error, even though this only affects old browsers.