add "Segoe UI Symbol" in markdown CSS font-family

[thyecust]

Hi, currently I notice that GitHub markdown uses this CSS font-family

.markdown-body {
    font-family: -apple-system,BlinkMacSystemFont,"Segoe UI",Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji";
    font-size: 16px;
    line-height: 1.5;
    word-wrap: break-word;
}

I suggest to add Segoe UI Symbol in the last. This font-family cannot render characters like U+20D7 (and many other characters). I use U+20D7 as vector symbol.

[theglobehead]

It looks like, you can use the symbol.
If you can see these symbols, you can try copy pasting them "◌⃗", "◌"