If you embed a webpage on a dashbaord all URL actions on that dashboard will attempt to change the embedded webpage. You either need to make them both open in a new window or have the 2nd one on a different dashboard. I've had this situation before too when I wanted to load an image from the web and have a webpage open - I ended up bringing those images in as custom shapes to get around this. Just in case that is what you are trying to do.
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