@kademi/keditor/src/keditor/utils/exitFullscreen.js

KEditor is a jQuery plugin which provides a content editor with drag n drop, configurable contents

export default () => {
    if (!document.fullscreenElement) {
        return;
    }
    
    if (document.exitFullscreen) {
        document.exitFullscreen();
    } else if (document.mozCancelFullScreen) { /* Firefox */
        document.mozCancelFullScreen();
    } else if (document.webkitExitFullscreen) { /* Chrome, Safari and Opera */
        document.webkitExitFullscreen();
    } else if (document.msExitFullscreen) { /* IE/Edge */
        document.msExitFullscreen();
    }
};