I have no idea if this is your issue, but I have run across an issue like this with a couple of image hosting sites I used. I had images / textures hosted on imgur and flickr free accounts that would load one minute and not the next. I also noticed it was random images that would come and go, just like what your having an issue with. I searched the internet to see if there was a fix for this issue and really didn't find anything except one possibility. I have no idea how this works, but on free image hosting sites, imgur and flickr included, if a certain image or images aren't viewed in a period of time they delete it or break the link to it. I found with flickr that if you visit your account from time to time it alleviates this issue. As far as imgur goes, I had to move everything to my paid account on another image hosting site to cure the issue. Good luck.
"Built into each of us is a little calculator that can make judgments that will never appear on a piece of paper. And sometimes you know something's right, you can't prove it to anybody, or you know something's wrong. Little ethical circuit breakers you carry around inside...so I go with my instinct."
Honorable General Colin Powell
Born: April 5, 1937, Harlem, New York, NY
Died: October 18, 2021, Walter Reed, Bethesda, MD
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