Would it be possible to add an option and icon for Steam Controller specific button prompts/glyfs?
The Steam Controller's button icons are distinct in several ways from the general xbox buttons, As they have their unique and distinct from the general xbox icons. For example, you can see in the images below the button prompts show icons for unique features and properties of the steam controller, , like the gyro, touchpad's, buttons at the end of the triggers, and grips.
There's also a number of games out there that use steam Controller specific prompts, because they've implemented them directly via the Steam Controller API (SCAPI). For example:
Team Fortress 2
Left for Dead 2
The Witcher 3: Wild Hunt
Cook, Serve, Delicious!
Defender's Quest: Valley of the Forgotten
If you want to see the official button prompts that Valve has made and have suggested devs use directly in Steam, and see how they're different from the xbox prompts, navigate to:
If they are decided to be added, could to add them to the input settings guide too, as well ass add the new "Simultaneous controller+KB/M" setting to the guide, as that's recently been added, but not to the guide yet, and is highly relevant to the Steam Controller :)
Here's some images of the distinct Steam Controller button prompts: