The aspect ratio of the tablet and the screen display mode are not corrected or corrected incorrectly! Nowadays, there are many widescreen monitors and widescreen tablets, and the aspect ratio is not corrected. It will not work if the board is changed to the same aspect ratio as the screen through software.

The problem is, and if you can draw without it, you don’t need a wide-screen LCD. It’s normal for the aspect ratio to not match the sign or the color correction to be wrong. It’s best to use the ICC curve to calibrate the display!