When a problem is intermittent and the logs show no useful information, a massive amount of low-level detective work is needed to find the answer. This effort is currently in progress. Please be patient, no-one is ignoring the issues.Hopefully, sometime in the not too distant future someone will offer an explanation.
Thanks for that Andreas. That is very useful.Here is what I noticed:
This image link is from a SOTD post
Removing the trailing %2F=&escpb=184-0 fixes the link
and that link actually works.
Where that stuff comes from I have no idea. Admins might want to look at this.
Also, some slashes are encoded as %2F, some are not.