There is no built-in way to do this. The extensibility model for Explorer panels sets a 1: 1 ratio between wires and tabs. There are many reasons for this, and often you have to deal with the easiest way to switch from IE6 to a modern tabbed web browser. Think of an OLE-based architecture: first you have your site object defined by IObjectWithSite. You are using a polling site for things like IWebBrowser2, current IHTMLDocument2, etc. Often extensions cache these pointers when they receive them. So you want a 1: 1 match.
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