`marker_mark` is used for colors of the markers in the marker margin, not in the text. What you see is probably the `marker_search`, for which only the background is used. See http://www.geany.org/manual/#id4 and the values there.
--- Reply to this email directly or view it on GitHub: https://github.com/geany/geany/issues/916#issuecomment-188535248
