diff -up plasma-desktop-5.5.3/kcms/kfontinst/lib/FcEngine.cpp.font_preview plasma-desktop-5.5.3/kcms/kfontinst/lib/FcEngine.cpp
--- plasma-desktop-5.5.3/kcms/kfontinst/lib/FcEngine.cpp.font_preview	2016-01-06 06:12:23.000000000 -0600
+++ plasma-desktop-5.5.3/kcms/kfontinst/lib/FcEngine.cpp	2016-01-09 09:53:10.864286301 -0600
@@ -537,7 +537,14 @@ QImage CFcEngine::Xft::toImage(int w, in
     if (!xImage) {
         return QImage();
     }
-    return QImage(xImage->data, xImage->width, xImage->height, xImage->stride, QImage::Format_ARGB32_Premultiplied, &cleanupXImage, xImage);
+    QImage::Format format = QImage::Format_RGB32;
+    switch (DefaultDepth(QX11Info::display(), 0)) {
+        case 32: format = QImage::Format_ARGB32_Premultiplied; break;
+        case 16: format = QImage::Format_RGB16; break;
+        case 8: format = QImage::Format_Grayscale8; break;
+        default: break;
+    }
+    return QImage(xImage->data, xImage->width, xImage->height, xImage->stride, format, &cleanupXImage, xImage);
 }
     
 inline int point2Pixel(int point)