I am using \buildtextaccent to create a couple of characters that have no Unicode equivalent. They are scribal abbreviations that made it into early typesetters works. In this case, the abbreviation are for Latin que, which looks like a q with a small ezh appended in a subscript position, and q with an acute accent, both of which are used in some 17th century works I am dealing with. An example of the abbreviation with the ezh and accent can be seen at https://books.google.com/books?id=hHNVAAAAcAAJ&pg=PA6#v=onepage&q&f=false in the sixth line of the paragraph beginning “Yea but”.

It seems that \buildtextaccent\textacute q (or \buildtextaccent´q) moves the q to the right within the character’s bounding box. The following example (and attached resulting pdf) demonstrates this. Lines 1 and 2 show the string with and without the \buildtextaccent, and lines 4 and 6 repeat that in italic.  The strings are the same width, but the q is moved right. Lines 3 and 6 show a manual kerning of the q to improve appearance.

This happens with many fonts, but not all (I do not see it with Computer Modern). I am using Win 10Pro x64 with ConTeXt  ver: 2015.09.04 11:00 MKIV beta  fmt: 2015.9.5  int: english/english.

I suspect that this is not intended, but I am not sure.

I would also love to raise the accent a bit. Suggestions? I can live with it as it is and manually kern as needed. There are very few instances of these abbreviations that need to be dealt with.
% macros=mkvi engine=luajittex

\starttexdefinition boxWidth #STR
  \setbox0=\hbox{#STR}\the\wd0
\stoptexdefinition

\starttexdefinition Dicitque
  Dicitq\kern-0.070em\low{ʒ}\autoinsertnextspace
\stoptexdefinition
\starttexdefinition DicitqueK
  Dicit\buildtextaccent\textacute q\kern-0.070em\low{ʒ}\autoinsertnextspace
\stoptexdefinition
\starttexdefinition DicitqueKK
  Dicit\kern-0.060em\buildtextaccent\textacute q\kern-0.070em\low{ʒ}\autoinsertnextspace
\stoptexdefinition

\starttexdefinition idque
  idq\autoinsertnextspace
\stoptexdefinition
\starttexdefinition idqueK
  id\buildtextaccent\textacute q\autoinsertnextspace
\stoptexdefinition
\starttexdefinition idqueKK
  id\kern-0.060em\buildtextaccent\textacute q\autoinsertnextspace
\stoptexdefinition

\setupbodyfont[ebgaramond,12pt]

\starttext
\startitemize[n,joinedup,packed]
\item \Dicitque \qquad\boxWidth{\Dicitque}\par
\item \DicitqueK \qquad\boxWidth{\DicitqueK}\par
\item \DicitqueKK \qquad\boxWidth{\DicitqueKK}\par
\it
\item \Dicitque \qquad\boxWidth{\Dicitque}\par
\item \DicitqueK \qquad\boxWidth{\DicitqueK}\par
\item \DicitqueKK \qquad\boxWidth{\DicitqueKK}\par
\stopitemize
\startitemize[n,joinedup,packed]
\item \idque \qquad\boxWidth{\idque}\par
\item \idqueK \qquad\boxWidth{\idqueK}\par
\item \idqueKK \qquad\boxWidth{\idqueKK}\par
\it
\item \idque \qquad\boxWidth{\idque}\par
\item \idqueK \qquad\boxWidth{\idqueK}\par
\item \idqueKK \qquad\boxWidth{\idqueKK}\par
\stopitemize
\stoptext
--
Rik