Determine whether your television or external display is cropping outer desktop edges due to legacy overscan zooming. Precise 1-pixel outer borders, corner markers, and high-frequency checkerboard patterns verify true 1:1 pixel mapping.
Web browsers cannot query your television's internal firmware picture mode or overscan aspect ratio setting. You must observe the edge boundaries with your eyes and adjust your television's remote control picture settings accordingly.
View detected resolution, color depth, pixel ratio, and HDR capabilities of your display.
Detect non-uniform stretching, egg-shaped circles, and aspect ratio mismatches.
Check display scaling, subpixel font rendering, and edge sharpness with 1-pixel alternating line patterns.
