I'm trying to use the screen capture function to capture short clips.  No matter what I try, I get a popup box when I select "start capture" that says "To Stop Capture, press F10....".  No matter what I do, that popup always actually gets recorded in the clip.  I can't find a way to disable the popup, I've tried using the shortcut keys to record, and I'm stuck.  Any thoughts on how I can capture a screen clip without having it record the initial pop-up box?  I'm hoping this is user error, but it's really frustrating.
Thanks for the help.
I've attached a screenshot of the popup as well as a sample clip that shows the popup.