An app called SISR will let you use the Steam controller with pretty much anything.
I linked this video to the exact time you need (34:36) that quickly explains how to set it up.
When you have SISR active, the controller turns into an Xbox 360 controller.
However, you can hold down the Steam button and use the right trackpad to use the mouse with the left and right triggers acting as the mouse buttons.
If you want the controller to act like a Steam controller again, go to your system tray in the bottom right of Windows and exit out of SISR.
Here's the app. Enjoy!
SISR (Steam Input System Redirector; pronounced "scissor") is a tool that allows users to redirect Steam Input configurations to a system level, either on localhost or even over the netwo...
github.com