Last modified: 2014-05-30 18:02:20 UTC
The image display size sent to the browser is incorrect when the image is not thumbnailed. A test page for this can be found here: [http://en.wikipedia.org/wiki/User:Feldmahler] The first image should be resized to fit into a 500x200 box, but instead it is resized to fit outside a 500x200 box. In other words, the image ''minimal'' size becomes 500x200 instead of the ''maximum'' size. The specification calls for the <nowiki>[[Image:Foo.bar|123x456px]]</nowiki> format to mean the maximum size and not the minimum size: [http://en.wikipedia.org/wiki/Wikipedia:Extended_image_syntax#Size]
If I'm not mistaken, the issue here is that the image isn't getting thumbnailed server-side due to its large pixel size; due to problems with resizing large PNG images, we have server-side resizing disabled for very large PNG images. Then, in the code path for displaying images scaled client-side, the box-fitting scaling mode doesn't appear to be treated correctly: only the width parameter is taken into account, rather than the width and height specified for the box.
Actually, I already knew from some devs talking to me on IRC that images larger than 12MP are not thumbnailed; I'm fine with that :) The problem is the second issue you were talking about, with the height not taken into account.
Moved to the 'JavaScript' component. It doesn't seem to be a parser bug, it seems to be a bug in the client-side javascript scaling.
There is no such thing as "client-side javascript scaling" in core MediaWiki, as far as I know.
