User:Subfader/PNG thumbs unsharp

https://bugzilla.wikimedia.org/show_bug.cgi?id=29659

PNG is the desired format for screenshots etc., but PNG thumbs are unsharp and blurry.

JPG thumbs of PNGs are sharper but have more artifacts when you look close, but still better than unsharp PNG thumbs.

PNG (original: 24 bit) JPG (original: TrueColor, q95 from PNG)