Thumbnails no longer appear in the OSM wiki

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1

I have noticed that thumbnails that used to render correctly in OSM wiki articles no longer do, so

[[File:2023 decree boroughs of Arkadag city.pdf|thumbnail|right|PDF file containing Russian, Turkmen, and English texts of decree creating two boroughs in the city of Arkadag.]]

now yields

File:2023 decree boroughs of Arkadag city.pdf

and not an image with a link to the object. Is there a new way of formatting thumbnail entries?

2

PDF thumbnails are currently broken because of a bug in MediaWiki: