If a browser was open before launching editor, and then (without having used that particular browser for a test) you close the browser and open another one before starting to record, once you start recording there is an unhandled COMException in BeginRecordingDialog.cs, at populateBrowserCheckedBox()
I cannot reproduce at my workstation.
Analia will take a look because she can reproduce the issue.
Error occurs when the record button is pressed right before the new browser finishes loading.