Archive for April, 2022

Use Synaptics touchpad while typing (Windows)

Sunday, April 24th, 2022

Windows laptops are consistently a worse experience than MacBooks, a large part of which has to do with the behavior of the touchpad. After installing Windows 11 on a ThinkPad X1 Carbon (3rd gen), I was recently dumbfounded by the inconsistency of the built-in trackpad and mouse buttons. Specifically, left clicks seemed to be dropped at random, which is infuriating. After a couple of weeks, I realized that it isn’t actually inconsistent: left clicks are consistently disabled for a second or so after typing on the built-in keyboard. The same thing goes for the touchpad.

Worse than a terrible default setting is a default setting that the user cannot override. The Synaptics settings window has a lot of options, but none that fix this atrocious behavior, which makes it almost impossible to use programs that require frequent switching between the keyboard and the mouse (which is, like, almost all graphical applications).

Fortunately, there are apparently (1, 2) some registry keys that control this behavior! Specifically, these two:

  • HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\PrecisionTouchPad\AAPThreshold
  • HKEY_LOCAL_MACHINE\SOFTWARE\Synaptics\SynTP\Defaults\PalmKms0, PalmKms1, …