"The mature and responsible thing to do would have been to add a content security policy to the page", he wrote. "I am not mature so instead what I decided to do was render the early 2000s internet shock image Goatse with a nice message superimposed over it in place of the app if Sqword detects that it is in an iFrame."
I submit the Internet axiom of: there's times and places for a measured and reasonable response, and the other times are funny af.
Let this be a lesson to you—if you are using an iFrame to display a site that isn't yours, even for legitimate purposes, you have no control over that content—it can change at any time. One day instead of looking into an iFrame, you might be looking at an entirely different kind of portal.