Hello list, The following example does not compile, complaining “Missing number, treated as zero needed to see a number, look up 'weird error' in the index to The TeXbook”: \setuphead           [chapter]                      [                       textstyle=cap,                      ] \starttext \startchapter        [title={Oops!}] \input knuth-gpt \par \stopchapter \stoptext Replacing the textstyle /cap/ by any of /bold/, /slanted/, /smallcaps/, and /italic/ results in a clean compilation but the indicated style is not applied. Using a style description like /em/, /\em/, /bf/, /\bf/, /\sc,/ does produce the suggested result. The wiki and mail repository are full of examples with the former style names. Using /style=cap/ (which would change the number as well) also results in a failed compilation, while using /style=bolditalic/ works as it should. ConTeXt  ver: 2023.09.26 18:19 LMTX  fmt: 2023.10.9  int: english/english -- Rik