Wikimedia Bugzilla is closed!

Duh, misclick.

MediaViewer displays a placeholder image (the small-resolution thumbnail of the same image, enlarged and blurred) while the real image is loading. To make the improve the usefulness of the placeholder and give a stronger sense of progress, the real image should be positioned on top of the placeholder (instead of the current mechanics of replacing it when the loading has finished).

For non-progressive images, the image is rendered gradually from top to bottom by most browsers, so this would result in the placeholder gradually becoming sharp from top to bottom. Romanski made a simple demo: http://jsfiddle.net/Czwpu/1/

For progressive images, the placeholder would not be visible at all (or just for a very short time, until the lowest resolution is loaded). Example of progressive loading: http://pooyak.com/p/progjpeg/