Egyptoon wow, that's strange, my bad then.
could you please explain how i can see this?
Well, you can control the fullscreen scaling, heres the manual
Only has an effect when a fullscreen mode is in use (whenFullscreen in browser is not Off). High quality mode renders at the full resolution of the screen. Low quality mode first renders at the project Window Size, and then simply stretches the result to fill the screen. Low quality mode often improves performance on low-end systems and is often suitable for retro-style pixellated games with Point sampling. However text, downscaled sprites and WebGL shaders appear with better quality and detail in high quality mode.