Thanksncsa's post https://focus-on-photography-forum.net/threads/post-stairs-inside-and-out.193/page-18#post-130897 seems to have the issue
As discussed, other sites running XenForo (but an older release than FoP) is not showing the same symptom... apparently these older sites use some form of plugin for XenForo which is no longer required with their current branch ..?
Flickr use to have these image servers (staticflickr.com, farm1.staticflickr.com, or subsequent farms)
It has become more noticeable in the past few weeks, even with two images posted together, one would load and the other simply fails - so editing the post to remove the red-x one.
A change in the captures is the sensor mp has increased to 60mp but this seems to be a red-herring.. I have tried various iterations of the linked above stairs....
Another aspect could be that LrC is involved and was also updated ... the export to Flickr may have also changed an element of the image file format
Some examples
Q3 43 (60mp)
Stairs by Neil, on FlickrThis failed to load in the original 'windows' thread
L1001156.jpg by Neil, on FlickrSL2 (47mp)
Q3 43 by Neil, on Flickr
Southbank by Neil, on Flickr
