Solution:
Put the keyboard on it, too, and the keyboard drawer is used as a drawer; In fact, many people are like this, and keyboard drawers are often extremely uncomfortable and unhealthy to use;
DIY is a mouse clip, but the moving range of the mouse is still relatively large, so the difficulty is not small. (and this posture is not very good, not recommended)
Buy a mouse tray that can be fixed on the chair.
Personally, I suggest the first.