Hi Tobias,
The problem is with Fodler Gallery plugin. It is not compatible with RL required syntax. Unfortunatelly this plugin seems not being under developed anymore. But if you do small change in one of the files, you’ll be able to use it with recent RL, including PhotoSwipe addon.
1. Go to Folder Gallery plugin on your site.
2. Find foldergallery.php
3. Go to line 449
4. Change this part:
$gallery_code .= '<a rel="lightbox[' . $lightbox_id . ']" data-lightbox-gallery="' . $lightbox_id . '" title="' . $thecaption . '" href="' . home_url( '/' . $folder . '/' . $pictures[ $idx ] ) . '">';
into this:
if ( function_exists( 'Responsive_Lightbox' ) && Responsive_Lightbox()->options['settings']['script'] === 'photoswipe' ) {
$image = getimagesize( ABSPATH . $folder . '/' . $pictures[$idx] );
$gallery_code .= '<a data-rel="lightbox[' . $lightbox_id . ']" data-lightbox-gallery="' . $lightbox_id . '" title="' . $thecaption . '" href="' . home_url( '/' . $folder . '/' . $pictures[$idx] ) . '" data-size="' . $image[0] . 'x' . $image[1] . '">';
} else {
$gallery_code .= '<a data-rel="lightbox[' . $lightbox_id . ']" data-lightbox-gallery="' . $lightbox_id . '" title="' . $thecaption . '" href="' . home_url( '/' . $folder . '/' . $pictures[$idx] ) . '">';
}
And it should work fine.