The resources tab of the developer tool that comes with Chrome/Safari shows that all background images within the CSS file get downloaded, regardless of whether or not they are shown.
So the CSS sprites file overwrites rule is used to display the image, but the image file is still downloaded in the background.
I guess it's just being smart - the images might get used as some point, eg with a javsascript event.

This isn't an issue with Firefox or Internet Explorer.
I ran a network sniffer to confirm this.
It's only a minor issue

Comments

alanburke’s picture

alanburke commented

If the method for generating the files changes as in #849508: Fails on aggregated CSS files - Plan of attack.,
this can be avoided.

dmitriy.trt’s picture

dmitriy.trt commented
Status: Active » Fixed

According to Resource Tracker in Chrome original images are not downloading, see #849508: Fails on aggregated CSS files - Plan of attack.

http://drupal.org/cvs?commit=394188

Status: Fixed » Closed (fixed)

Automatically closed -- issue fixed for 2 weeks with no activity.