Over Bluetooth a linked DualShock 4 or DualSense switches to its full
reports, which the browser's gamepad doesn't read, so the PS4 got no
input from it. While linked, its buttons, sticks and triggers now come
from those reports, over USB and Bluetooth alike.
A fault in the experimental code no longer stops the page's input loop,
and "How to turn it on" only shows when the page is insecure.