KIconLoader problem with KFontInst

[Marco Martin]

Hi all,
there is a weird problem with the kf5 version of the KFontInst kcm module.
if you load it from SystemSettings, then going back all icons of 
systemsettings categories disappear.

since kfontinst has some "own" icons, I see it's doing this in 
KCmFontInst.cpp:
KIconLoader::global()->addAppDir(KFI_NAME);
KIconLoader::global()->reconfigure(KFI_NAME);

if i put this patch in KIconThmemes, it appears to solve the issue:
http://paste.opensuse.org/52060340

but still, it doesn't feel quite right..
any idea on what the issue actually is?

-- 
Marco Martin