Separated this into another thread because this is probably a different issue than the other one.
Listly is 100% compatible with https with just a few caveats that has to do with images that are initially added to an item. When you add an image to an item with a http link, Listly will try to copy that image to Listly CDN and deliver it via https. This issue you see happened because the image on pinterest was not accessible to Listly to convert/move a copy of the image to our own CDN. We updated that item with a new image and the issue is gone. If you see mixed content issue with an image, please updated the item with a new image and it should be fixed.
Are there other instanced on your site where a list does not load?