@erikvold
Using UserStyles with Jetpack
This morning I created a Jetpack module which makes it dead simple to include userstyles in a addon.
How to use
Here's a example:
In this example, the addon is loading a userstyle/css file located within it's "data" folder.
If you'd like to use this module, then it is available on github here for those of you that know how to use the addon-sdk. Otherwise, the module is also available on the Addon Builder here, and I have a example of how to use the module in the Addon Builder here. So give it a try!
UserStyles
For those of you that don't already know, a userstyle can be used to modify the css of any webpage (aka content) or Firefox window (aka chrome), and has been made popular by Stylish add-on for Firefox for which there is a site, userstyles.org, where thousands of userstyles can be found.