How to change browser focus from one tab to another

Question

I have a JavaScript chat client running in one browser tab (call it tab A). Now when a message arrives the user might be on another browser tab (call it tab B). I\'m looking

Answer 1

It is not possible - due to security concerns.

unless by "tab" you mean a window and a popup window that (due to browser preferences) opened up in a new tab. If this is the case, then yes you can.

//focus opener... from popup
window.opener.focus();

//focus popup... from opener
yourPopupName.focus();