edException(func) {
        try {
            func();
        } catch (e) {
            if (e instanceof DOMException) {
                printlnBuffered(`${e.name}: ${e.message}`);
            } else {
                printlnBuffered(e.toString());
            }
        }
    }

    printCatchedException(() => {
        globalObserver.observe();
    });

    printCatchedException(() => {
        globalObserver.observe({ entryTypes: [], buffered: true });
    });

    printCatchedException(() => {
        gl