I finally saw it --- but only after I changed User-Agent header to a more common one. It seems like some thought was put into this to make it show only for "normal" users, and not unknown/crawler/etc. (I hit Cloudflare CAPTCHAs all the time.)
In case you're curious, many years ago when Imageshack started restricting images based on Referer and other things, I had a proxy rule created to bypass that --- appropriately named ImagesHack --- and one of the things it did was change the UA too.
In case you're curious, many years ago when Imageshack started restricting images based on Referer and other things, I had a proxy rule created to bypass that --- appropriately named ImagesHack --- and one of the things it did was change the UA too.