Martin Leurs

Thank you, i switched to WP Featherlight, that solved the issue for me.

With [slb_group] you need to add one html-block before and one html-block after every gallery-block.

…
html block > [slb_group]
gallery block with images
html block > [/slb_group]
…

Regards
Martin

Thank you very much, it works. ??

Sure, martinleurs.de/wp