diff --git a/scripts/render_index.sh b/scripts/render_index.sh
index 0a4ccf32..3d2c0753 100755
--- a/scripts/render_index.sh
+++ b/scripts/render_index.sh
@@ -17,7 +17,7 @@ cat <<EOF>index.html
 EOF
 for f in $@; do
     img=$(basename $f .html).png
-    phantomjs $(unset CDPATH && cd "$(dirname "$0")" && echo $PWD)/rasterize.js $f $tmpdir/$img 1200px*900px
+    QT_QPA_PLATFORM=offscreen phantomjs $(unset CDPATH && cd "$(dirname "$0")" && echo $PWD)/rasterize.js $f $tmpdir/$img 1200px*900px
     convert $tmpdir/$img -resize 400x300 thumbs/$img
     cat <<EOF>>index.html
 <p style='text-align: center'>