How should I interpret the fact that a Unicode code point is shown in two completely different ways in two different terminal emulators?

This is kind of a spin off from [an older question I asked](https://unix.stackexchange.com/questions/715076/how-can-i-have-colored-emoji-in-urxvt) . Here's the screenshot from that question: - In the bottom left is [URxvt](https://wiki.archlinux.org/title/Rxvt-unicode) , and you can see a lighting bolt-like icon at the beginning of the prompt, that's "\ue00a"; - in the bottom right is xfce-terminal from [Xfce](https://wiki.archlinux.org/title/Xfce) , and you can see that it renders the very same "\ue00a" Unicode point in a very different way! I was under the impression that when I read something like "\ue00a", "\u263b", "\u1d43d" and so on, I'm most likely looking at the identity of a symbol, as defined by Unicode. However, how strange would the definition need to for it to allow 2 terminal emulators to show it so differently? Incidentally, I don't know how much of this is due to the terminals and how much to the fonts. I am asking this question (like the other I linked) in order to get a better understanding of the whole matter.