Hello;
same thing for me using Firefox.
Why do you need to have your file templates/4swim/media/jpg.html like this?:
<!-- Template file for GIF Files -->
{if set}<!--<b>{lang_wm_gloss}</b><br /><br /><a target="_blank" alt="{image_name}" href="{media_src}">--><img src="image.php?v={media_src}" border="1" alt="{image_name} :: Wallpaper"/><!--</a><br />-->{endif set}
<!--{if notset}<img src="{media_src}" border="1" alt="{image_name}"{width_height}/><br />{endif notset}-->