This is TridentSense's own controller page, running in your browser. Plug in a DualSense, DualSense Edge, DualShock 4 or Switch Pro controller (USB or Bluetooth), press Connect a controller, and try its light bar, player lights, rumble, adaptive triggers and Trigger Lab, and see its input live. Only the Controllers section is open here: the rest of TridentSense comes with the app.
Your browser cannot connect to controllers directly. Open this page in Chrome, Edge or Opera on a computer for the full demo. Here, a controller's buttons and sticks are shown, and simple rumble where your browser has it.