Tests that captureScreenshot works
{"format":"png","clip":{"x":0,"y":0,"width":50,"height":50,"scale":1}}
green: {"r":0,"g":128,"b":0,"a":255}
red: {"r":255,"g":0,"b":0,"a":255}
{"format":"jpeg","clip":{"x":0,"y":0,"width":50,"height":50,"scale":1}}
less than 20% bad pixels: true
{"format":"webp","clip":{"x":0,"y":0,"width":50,"height":50,"scale":1}}
less than 20% bad pixels: true