I bet this this related to thumbnail chaining (T69525)
How to reproduce:
- Upload a JPEG file (1,024 × 768 pixels) to Wikimedia Commons
- Try to get a 500px thumbnail (e.g. writing `[[File:<name>|500px]]` on a random page and hitting "preview")
When attempting to view this thumbnail, you'll get an error message similar to the following
> Error generating thumbnail
> Error creating thumbnail: convert: Empty input file `/tmp/transform_e680fcd173fa-1.jpg' @ error/jpeg.c/EmitMessage/242.
> convert: missing an image filename `/tmp/transform_4d401c5ab2ee-1.jpg' @ error/convert.c/ConvertImageCommand/3011.
> Error code: 1
I have already reproduced this with [a test image](https://commons.wikimedia.org/wiki/File:Test_rillke.jpg). A couple of other images that are affected:
- [[ https://commons.wikimedia.org/wiki/File:Transit-lune-sat--22-mai-01.jpg | File:Transit-lune-sat--22-mai-01.jpg ]] ([[ https://upload.wikimedia.org/wikipedia/commons/thumb/e/e3/Transit-lune-sat--22-mai-01.jpg/838px-Transit-lune-sat--22-mai-01.jpg | thumbnail ]])
- [[ https://commons.wikimedia.org/wiki/File:Da_Vinzy_-_moon_%28by%29.jpg | File:Da Vinzy - moon (by).jpg ]] ([[ https://upload.wikimedia.org/wikipedia/commons/thumb/b/bb/Da_Vinzy_-_moon_%28by%29.jpg/500px-Da_Vinzy_-_moon_%28by%29.jpg?foo | thumbnail ]])
- //more can be provided if necessary//
There all thumbnail sizes up to [[ https://upload.wikimedia.org/wikipedia/commons/thumb/e/e3/Transit-lune-sat--22-mai-01.jpg/479px-Transit-lune-sat--22-mai-01.jpg | 479px ]] for File:Transit-lune-sat--22-mai-01.jpg appear to render; at [[ https://upload.wikimedia.org/wikipedia/commons/thumb/e/e3/Transit-lune-sat--22-mai-01.jpg/480px-Transit-lune-sat--22-mai-01.jpg | 480px ]] I receive said error.