The musical notation is an especially brutal example of something bad that persists for ages

The hex colors are also awful, but even the newer HSL type of system doesn't go far enough to be convenient - the hue shouldn't be some magical wheel where you have to remember at whch exact point each color is located, you already remember rainbow letters from your childhood, those should be used (then you can add numbers to signify deviation from the pure hue)!

> Whether or not it’s not an A/B test, I’m really hoping that GitHub is collecting enough metrics so they can evaluate the impact of this design on user experience at scale

Why would you hope that if there isn't even an easy feedback mechanism? Metrics can't read your mind like that

P.S. Tangentially related, you can use your favorite editor with an extension like GhostText not to suffer a big part of the awfulness of all those text input forms with the added benefit that you are highly unlikely to ever lose your text again since if the web form misbehaves you'll still have a backup in the text editor temp buffer