When I started building a browser-game catalog, my first acceptance test was simple: open the page, wait for the iframe, and confirm that something appeared on screen. That test was wrong. A browser game can display a polished launch screen and still be unusable. The first click may do nothing. Keyboard controls may never reach the game. Touch input may fail on mobile. The upstream provider may redirect to a branded landing page. A game that worked last week may silently change its embed p...