\definefontsize[a]%
\definefontsize[b]%
\definefontsize[c]%
\definefontsize[l]%
\setupbodyfontenvironment[default]%
    [%
        a=1.200,
        b=1.440,
        c=1.728,
        l=8.916
    ]%
%

\setuplabeltext[chapter=\strut]
\setuphead[chapter][style=\ssc,placehead=yes,expansion=yes,page=yes,
numbercommand=\groupedcommand{}{\blank[1cm]},
alternative=middle,
numberstyle=ssl,
numbercolor=green,
strut=yes]

\starttext

    \completecontent
    
    \chapter{Test}
        \input knuth

    \chapter{Test}
        \input knuth

\stoptext

The problem I'm facing, is anytime a chapter title is called, such as "Content" in complete content, or something in the appendix, such as one of the indexes, no number is printed above, so the vertical distance from the top of the page to the top of the chapter title changes. I need these to be consistent, as there is a background image, with vertical lines.

Basically, if I call \chapter{}, it appears perfectly aligned vertically on the page, with no other settings. But when calling \completecontent or a similar title that won't get a number, because the number isn't placed, it is vertically higher on the page, but I need it to be printed the same height, as it it had an invisible number.

I've tried adding strut (the code has it in two places), but don't know if I've used it appropriately, and it didn't solve the problem.

--Joel