Browser in Outlook 2007 window

My default browser is Mozilla Firefox. I was playing with customizing the Outlook toolbar and found that if I use the search icon - BING opens in the MS outlook window and the links stay in the window. However, if I use the browser command, Firefox opened properly. Is there a method of keeping the browser in MS Outlook only ?
 
This and other reasons are why I never use these "Toolbar" add-ons - - they just get in the way and cause problems - - IMO
 
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