What makes you think its Coldfusion causing this?
Im not sure what popup you are talking about though, could you provide a screen shot?
The Debugging Output Format has been changed to use "dockable.cfm" instead of "classic.cfm" in ColdFusion Administrator. You'll need to switch it back. Go to the Debug Output Settings page in CF Administrator (under the DEBUGGING & LOGGING section). On that page, look for the Custom Debugging Output heading - the first item below the heading is Select Debugging Output Format. Click the pulldown and switch it from dockable.cfm to classic.cfm.
If you don't want any debugging info to appear (and if you should not show debugging info if you are in production), uncheck Enable Request Debugging Output.