Browser extension: is there a way to stop the loading of images?

In either Firefox/Chr开发者_运维技巧ome extension, is there a way to stop the loading of <img> before the browser actually starts loading them from a page?

The popular Web Developer extension for Firefox has this feature, under its images menu

In Firefox it is possible, in Chrome it in not possible yet, but this is a common request from extensions developers, so they are working on it (Chrome devs are mainly worried about performances hit).