Seams on desk pads won't mess up your mouse.

Probably not.

Modern optical mice handle slight texture changes without a hitch. The sensor is reading the surface, not the gap between two pads. As long as the pads are flush—no big raised lip or gap—the cursor won’t jump or stutter when crossing over.

The real culprit is usually a cheap pad that curls at the edges, or a pad that’s too thin and slides around. If you’re joining two pads, tape them together underneath with double-sided carpet tape. That kills any movement and levels out the seam.

If your mouse does freak out at a seam, it’s time for a new mouse.