Resolve the factory to open a stream with, or throw EventSourceUnavailableError.
The global is read on every call rather than captured at module load: a test (or a polyfill) that assigns globalThis.EventSource after import must still be seen.
globalThis.EventSource
Optional
Resolve the factory to open a stream with, or throw EventSourceUnavailableError.
The global is read on every call rather than captured at module load: a test (or a polyfill) that assigns
globalThis.EventSourceafter import must still be seen.