postinstall: fontconfig

[Thomas Klausner <wiz%NetBSD.org@localhost>]

Hi!

postinstall check on my system complains
...
fontconfig check:
        Broken fontconfig configuration found; please delete these files:
        [ 10-sub-pixel-rgb.conf]
...

but can't fix the problem:
# postinstall fix fontconfig
Source directory: /usr/src
Target directory: /
fontconfig fix:
        Broken fontconfig configuration found; please delete these files:
        [ 10-sub-pixel-rgb.conf]
postinstall fixes passed:
postinstall fixes failed: fontconfig

Also, the exact same file is still installed in a new from-scratch build:
# diff etc/fonts/conf.d/10-sub-pixel-rgb.conf  /etc/fonts/conf.d/
#

What's up with this?
How is the file broken and if so, why is it still installed by new builds?
 Thomas