Aside: the font that my browser is using for monospace has a mistake in its gylphs:
1db47ef2-3de0-47a8-b4cb-28d310f10872-image.png
The non-monospace font (in black) correctly shows U+266B ♫ as beamed eighth notes. The monospace font (in red) shows that same character as beamed sixteenth notes instead. Whoops.
No, my browser says it’s using DejaVu Sans Mono for fixed-pitch, and charmap shows that DejaVu Sans Mono has four separate glyphs for those notes.
80ece08d-4d00-43ba-8b7f-ac1b8571b218-image.png
And Notepad++, which is set to use the same font as well, shows the correct glyphs for those four characters
869ae6ca-141c-43f1-bde4-9f9d91a7039e-image.png
Oh, I bet that the forum stylesheets are overriding my font choices.
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Edit: Yes, the CSS has its own list of fonts before using what the browser is set at. How rude. 24c7109c-0a36-4420-abd1-a3dd122fd0ab-image.png
I don’t have Menlo or Monaco, so it would try Consolas, which doesn’t have that glyph, then Courier New, which doesn’t either, then monospace … so it should be trying DejaVu Sans Mono at that point… but doesn’t seem to be. Oh well, browser issue.