A related question: I added noto emoji fonts. Now on test page the vast majority of emojis show up in color using the noto font, while a few of them (e.g., "smiling face", "frowning face", and "skull and crossbones") show up in a much more primitive-looking font in black and white (could be one of the fonts in Xorg-fonts.tcz).
Not that I particularly care about the above "issue", but it is an opportunity for me to learn how to tweak font selection/priority when more than one font can be used to display a particular glyph.
So, how do I force all emojis in my web browser (Brave) to be rendered with NotoColorEmoji-Regular.ttf? This how-to looked promising:
https://askubuntu.com/a/1204262No luck with that, though. As with user
denshigomi, I get this as expected (so far so good):
$ fc-match -a | head -2
NotoColorEmoji-Regular.ttf: "Noto Color Emoji" "Regular"
DejaVuSans.ttf: "DejaVu Sans" "Book"
But the black and white emojis are still there when I close my browser and reload the test page! It seems the browser is ignoring fontconfig and following some other font selection algorithm.