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Hello Katherine, I hope I understand your question correctly. So you are using Google's Data Highlighter to mark up page elements on your site, but there is a pop-up window that you need to get rid of when using the highlighter? If you can't get rid of the pop-up when clicking on the X, have your developers temporarily disable it. If you turn off javascript on your browser it will probably kill the pop-up, but it would also probably keep GSC Data Highlighter from working. If you are trying to mark up the information within the pop-up, I'm not sure that's even possible with Data Highlighter. You would probably have to do that in the code on your site.