Images not showing on Safari

The plug-in worked great on Chrome, but is not working on Safari. I’ve started debugging – it looks like the the twentytwenty-wrapper div is not present in Safari, while it is present in Chrome. The div class directly wrapping the images (twentytwenty-container) has a height specification in Chrome and not in Safari. This is when logged in to WordPress.

If anyone sees this and has ideas/suggestions/fixes, they are welcome. I will debug more in the coming days and post more info (and maybe solutions) here as I find them.