Hello,

[Bug 36597] is about switching PDF thumbnails from jpeg to PNG. The change to PdfHandler extension is really straightforward:

https://gerrit.wikimedia.org/r/#/c/6802/

It feels like PNG is more suitable, but would like some other people input before merging this change in.

[Bug 36597] https://bugzilla.wikimedia.org/show_bug.cgi?id=36597