After dialog has closed, keyboard focus returns to the beginning of the parent window.
Please read the documentation to understand how these examples were created.
This dialog just opened on page load, preventing access to the main page underneath. Probably not what you were expecting, right? Right. This interaction should be avoided if at all possible.
Typically, a dialog should only be opened after an explicit user action, such as clicking a Dialog Button.
Updated: May 12th, 2019