The way sigils are highlighted by default in the default theme is very ugly:

It gets much better in the darcula theme:

I think that in the default theme, the colour for the sigils should be changed.
I assume you mean that you don't like the black background. You really need to be more specific than "ugly".
Yea, it is really hard to read on my screen. Contrasts hard with everything else. I'll come up with some colours I think look nice.
Ok, what do you think of an only #005700 foreground? It's a darker version of the string's #008000 color, because they are sort of like strings, but not.

Could also do a bold only #007366 foreground (darker than strings and a bit blue) . Strings are bold, so I think perhaps sigils should too?

edit: never mind, this is too similar.
Miss labeled branch for #751 as 693 instead of 683.
@nhooyr, Char List, String, and Sigil hues are 90掳 from each other (using HSB color system) on purpose to make them more obviously different. I'm going to drop the black background, but leave the color, #996C18 unless you can find a combination of Textual (Char List, String, Escape Sequence, and Sigil) attributes that have better readability.
Sounds good to me.
Also, you forgot to update the description for the sigil text attribute in your link.
Thanks @nhooyr, fixed it in #765