Perhaps you mean
https://forum.oneclickchicks.com/sho...22&postcount=2 . I occasionally had that "problem" a while back, usually from large pictures from flickr; when I tried to fix it (this was some years before the linked post) I found the versions that resulted had lost some resolution along with byte size,
and I noticed as you did that once the thumbnail was clicked on a "wrong" one the orientation was correct, so I decided it wasn't worth the aggro.