Testing All My PS5 Controller Buttons, Why Do A Few Of Them Not Show Up?

Both of these come from what browsers are given, not from your controller.

Browsers read controllers through the Gamepad API, which describes a standard layout of 17 buttons: four face buttons, two bumpers, two triggers, two centre buttons, two stick clicks, four D-pad directions and a home button. On a DualSense those map to Cross, Circle, Square, Triangle, L1, R1, L2, R2, Create, Options, L3, R3, the D-pad and PS. Anything outside that layout depends on the browser and operating system passing it through.

The mute button is outside it, and mainstream browsers do not pass it to pages, so it looks dead on any browser tester with any DualSense. The touchpad click sits in between: some browser and connection combinations report it as an extra button after PS and others do not, and USB and Bluetooth can differ. That is why you see it come and go.

So for your warranty check, use the browser for the 17 standard buttons, the sticks and the triggers, and use something with full DualSense support for the last two. On a PS5, the mute button lights up when pressed and the mic status changes on screen. Steam's controller settings also show the touchpad click.

If the mute light does not come on when you press it on a PS5, that is worth reporting before your warranty ends.