Button prompt images from "Xelu's FREE Controllers & Keyboard PROMPTS"
by Nicolae (Xelu) Berbece, https://thoseawesomeguys.com/prompts/

Released under Creative Commons 0 (CC0), free to use in any project.
Trimmed and resized by tools/make_glyphs.py.

The Steam Deck images (steam_deck/) are from "Input Prompts" by Kenney,
https://kenney.nl/assets/input-prompts

Also released under Creative Commons 0 (CC0). Trimmed and resized by
tools/make_glyphs.py --kenney.

keyboard/MB4.png and keyboard/MB5.png (the mouse's side buttons) are drawn from Xelu's
keyboard/Mouse_Simple.png by tools/make_mouse_side_glyphs.py, their numbers in Oswald
(bf/fonts, SIL Open Font Licence).
