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Wow, this is awful. Would you mind telling me what combination of settings/add-ons you have so that we can reproduce this? Our "no JS" fallback styles are not done in a very nice way at the moment: they rely on the browser reading noscript tags. We never did any testing with NoScript or similar add-ons, and I remember hearing somewhere that those sort of add-ons don't always evaluate noscript tags.
Thanks for your reply! - Chrome Version 57.0.2987.133 (64-bit) - No-Script Live 0.2.4 http://mybrowseraddon.com/noscript-lite.html - Privacy Badger 2017.4.19.1 FWIW Privacy Badger isn't blocking anything, I think this is all from script blocking. I notice that low-res images get sent by default, which suggests that the design conflates 'no script' with 'mobile'? That's not true at least in my case. Here's my browser…
Could also be javascript-powered lazy loading. Load the low res using HTML then swap out high-res when the user scrolls it into view