Comment by zinekeller

> However, eg. PowerPoint doesn't support OpenType (as far as I know).

Ironically, it is Microsoft which developed CPAL/COLR (at least intially), and this is the least atrocious format across colored suggestions. The other options are SVG-in-OpenType (Adobe/Mozilla; https://helpx.adobe.com/fonts/using/ot-svg-color-fonts.html), PNG-in-OpenType/SBIX (Apple; https://developer.apple.com/fonts/TrueType-Reference-Manual/...), and CustomBitmap-in-OpenType/CBDT (Google; https://fonts.google.com/noto/use).

All of them are now OpenType standards, for better or worse.