The HTMLInputElement.multiple property indicates if an input can have more than one value. Firefox currently only supports multiple for <input type="file">.
The HTMLTableElement.rows read-only property returns a live HTMLCollection of all the rows in the table. The rows included in the associated <thead>, <tfoot> and <tbody> elements.
The NavigatorConcurrentHardwaremixin adds to the Navigator interface features which allow Web content to determine how many logical processors the user has available, in order to let content and Web apps optimize their operations to best take advantage of the user's CPU.
The PromiseRejectionEvent.promise read-only property indicates the JavaScript Promise which has been rejected. You can examine the event's PromiseRejectionEvent.reason property to learn why the promise was rejected.
The PromiseRejectionEvent.reason read-only property is any JavaScript value or Object which provides the reason passed into Promise.reject(). This in theory provides information about why the promise was rejected.
The Selection.isCollapsed read-only property returns a Boolean which indicates whether or not there is currently any text selected; That is to say that the selection's start and end points are at the same position in the content.