Recently I downloaded a PDF copy of the article Electrical connector, from Wikipedia's PDF Rendering Option[[https://en.wikipedia.org/w/index.php?title=Special:Book&bookcmd=rendering&return_to=Electrical+connector&collection_id=eb633b1ec14fd07590dcdd6f9aed49de03b4be68&writer=rdf2latex&is_cached=1|Download as PDF]] and it struck my eyes that an image present in the main article Electrical connector#Keying the 3 images of examples for keyed connectors , are absent in the PDF output.
Though it is important part at the interior-portion of article. (I didn't checked, is there any text-portion missing. But I well-checked the 3 images are no-where in the PDF) .
I repeatedly downloaded >1 times, and every time the exactly-same, error-containing output obtained.
I've attached the PDF file here ...
Now, I logically assume , this-kind of error can taking place every now-and then.
So please diagnose the error. It was a single Wiki page. But the same could occur in a Wikibook.
if in 1 page there could occur 1 mistake, in a printed-book, >1 mistake can occur.