Under what circumstances might all images on the page load?

[sbgraphicdesign]

I've got a Shopify site that uses a theme (Debut) which integrates Lazysizes, however all images are loaded (and the class "lazyloaded" applied) upon page load, no matter where they are on the page:

Sample page: https://www.cardtoons.co.uk/products/cal001-wordsworths-lake-district-images-calendar-2022

I'm wondering therefore what might cause all images to be loaded; a javascript conflict perhaps, or page layout?

I've looked at page code for a couple of other Shopify sites that use the same theme, and they appear to have the same issue, so this could be an issue with the theme, or with Shopify in general, but hopefully someone here might be able to identify a cause. So I would definitely appreciate any ideas on where to go with this, thanks.

[sbgraphicdesign]

Okay, so it turns out the theme is lazypreloading images by default. Should have realised earlier.