Check if `passive` is supported via TypeScript

typescript-check-if-passive-is-supported.ts

/** In case your linter gives you a problem attempting to register listeners to `testEvent` */
declare global {
	interface WindowEventMap {
		testEvent: CustomEvent<{ event: any, options: any }>;
	}
}

/** Inspired by: https://developer.mozilla.org/en-US/docs/Web/API/EventTarget/addEventListener#Safely_detecting_option_support */
export const isPassiveSupported = () => {
	let passiveSupported = false;

	const fakeHandler = () => {
		return false;
	};

	try {
		const options = {
			get passive() {
				passiveSupported = true;
				return false;
			},
		};

		window.addEventListener('testEvent', fakeHandler, options);
		window.removeEventListener('testEvent', fakeHandler, false);
	} catch (err) {
		passiveSupported = false;
	}

	return passiveSupported;
};