First of all: WooCommerce has it’s own version of PhotoSwipe integrated. Using it together with Lightbox with PhotoSwipe may cause conflicts. Also see the FAQ of Lightbox with PhotoSwipe how to disable the plugin on WooCommerce product pages.
Furthermore I think you may have a serious performance issue with your database.
One change after 1.64 is to check the database for captions based on the image URLs. On 1.64 or older the captions only got extracted from the HTML code of the page – but this caused some captions not to be visible since not all galleries output captions in the same way and single images in a page may not have visible captions at all.
On https://www.vorhangbox.ch/vorhang-online-bestellen/tagvorhang-geneva-weiss-auf-mass-massvorhang/ there are about 24 linked images. Therefore the plugin had to execute about 72 database queries – 24 to get the cached image sizes, 24 to get the post IDs of the images and another 24 to get the captions for these IDs. On 1.64 it was only 24 database queries for the cached image sizes. If 48 additional queries cause a delay of about 5 seconds, the database is really slow.
For comparison: this page contains 205(!) images and there is no caching at all: https://arnowelzel.de/zurueck-aus-finnland. The complete page including all pictures usually does not take more then 2-3 seconds to load, even thow it executes about 615 database queries to build the page.
I’ll prepare an update where you can turn off the extraction of image captions from the database in the plugin. But you should really check if there is a performance issue with your server and also consider adding the example code to disable the plugin on WooCommerce product pages.
