Firefox won't display nggallery prev/next triangle

If you want Firefox (at least on a mac) to display your triangle navigation, search and replace all &#9668 with &#9666 and &#9658 with &#9656 in the php files. (I tried using the code ticks but it parsed it. The complete code will have a semi-colon at the end.) You’ll find them in gallery-carousel.php, navigation.php, imagebrowser.php, imagebrowser_exif.php and imagebrowser-caption.php. They will be smaller triangles but at least they won’t be invisible.