When I typeset the example at https://wiki.contextgarden.net/Command/definefirstline (reported below for your convenience), \setfirstline is applied to the whole first paragraph, which is laid out on a single line (hence, it is cropped at the edge of the page). Besides, the second \setfirstline is not applied at all, i.e., there are no small caps. If I comment out the first \setfirstline, then the second one does produce small caps, but again, a whole paragraph is set in small caps, not just the first line. $ context --version mtx-context | ConTeXt Process Management 1.03 mtx-context | mtx-context | main context file: /Users/nicola/Applications/context-osx-64/tex/texmf-context/tex/context/base/mkiv/context.mkiv mtx-context | current version: 2020.08.11 15:59 mtx-context | main context file: /Users/nicola/Applications/context-osx-64/tex/texmf-context/tex/context/base/mkiv/context.mkxl mtx-context | current version: 2020.08.11 15:59 Nicola %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \setupbodyfont [heros] %% important: smallcaps capable font! \definefirstline [italicfirstline] [ alternative=line, style=italic, ] \definefirstline [smallcapsfirstline] [ alternative=line, color=darkred, style=smallcaps, ] \starttext % \setfirstline[italicfirstline] \input knuth \par \setfirstline[smallcapsfirstline] \input knuth \par \stoptext %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%