Play link to files supported by WHATWG Video/Audio tag just like we play *.mpg, or files supported by plugins. Bug 422538 implemented support to play *.ogg files in <VIDEO> tag. See http://commons.wikimedia.org/wiki/Image:Fraser_island_australia_sand_track.ogg But still if we click on a link to the *.ogg source file it ask to download instead of playing it. Steps: 1. click http://upload.wikimedia.org/wikipedia/commons/6/64/Fraser_island_australia_sand_track.ogg Result: download prompt Expected: Play video