i was wondering too... and saw this post. ofc i tried disabling my adblocker, no difference - but i already thought the problem is somewhere else.

#1: either the vendor has the possibility to submit different thumbs for different pages, and some didn't do it for the public list
#2: or there is an issue with some images.

i think it's #2, if you right-click on a visible thumb, copy the image's url and open it in a new tab, you'll see the original. if you do it on an invisible thumb (link or img-break pic), when you open the url you get this error msg:

Fatal error: Call to a member function getSessionCount() on a non-object in /rn1/renderosity/builds/production_1419007539/element/insertnumusers.php on line 19

no clue what that means though ~ i don't know php.
but i also have the plugin "thumbnail zoom plus" (firefox) which opens a view of any thumbnail on any site, and when an original image doesn't exist any more, like often on goggel images, i see an alarm triangle... this happen here too on the invisible thumbs.

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