An object will be opened in the read-only mode if the object's ancestor or descendant is already open, or the User Object on its surface is already open, or a control inherited from it is already open. You will be prompted that the object is read-only when the object is opened, and a lock icon will be displayed in the tab header after it is opened. For a read-only object, you can change its UI in the painter, but you cannot save the changes, and you cannot change or save its scripts in the code editor.
