All files / utils supportsPassiveEvents.ts

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// via https://developer.mozilla.org/en-US/docs/Web/API/EventTarget/addEventListener#safely_detecting_option_support
 
let supportsPassiveEvents = false;
 
try {
    const options = {
        get passive() {
            // This function will be called when the browser
            // attempts to access the passive property.
            supportsPassiveEvents = true;
            return false;
        },
    };
 
    window.addEventListener("test", null, options);
    window.removeEventListener(
        "test" as keyof WindowEventMap,
        null,
        options as EventListenerOptions
    );
} catch (err) {
    supportsPassiveEvents = false;
}
 
export { supportsPassiveEvents };