Sudeenly working on pages but not posts or archives

Ever since updating to WP 4.0, Fancybox is not working on the main blog page (home) or any of the individual posts at my client’s site https://www.kimnovakartist.com (yes, the classic film star) It’s working fine on all the pages. Tried deactivating some plugins and couldn’t see that anything changes, only got worse. Haven’t tried deactivating the theme yet, because her site gets so many visitors. I’d have to do that late at night I guess. It’s strange, because even the cursor change from arrow to hand is not occurring over the small images that are linked to larger ones. Really need a hand with this, not sure from what I see what I should try next…
Thanks so much,
Hannah

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