Photoshop hint telling me to try rotating the canvas won't go away

You inserted a really annoying "Hey dummy, I bet you never used Photoshop before. Did you know you can rotate the canvas?" popup. There are two buttons on the popup: Get Started and No Thanks. The No Thanks button doesn't do anything. Escape will close the window, but only temporarily. If I switch to another document and switch back, then the popup reappears.