At MDG, we’ve worked on/are working on a number of Firefox themes for clients. Each time I’m asked what icons are needed, I scratch my head and scour around the UI making notes. I haven’t found any documentation on this. So this post is an attempt to document it for reference. If I am missing anything, please do let me know.
1) This document is coming from an implementation viewpoint, and not a design one, i.e. not concerned with what the icons look like.
2) Unless where specified, all images can be in PNG or GIF format, but PNG is preferred.
3) All chrome:// urls used as examples here are from the default Winstripe theme on Windows, but should also apply to other themes. They are listed to enable lookup for examples. If they appear as hyperlinks in this post, they may not work. You will need to copy and paste them into the Firefox location bar.
4) Items marked with an asterix (*) are viewed as being compulsory to change for a new theme. All other are optional.
5) This applies to Firefox 1.5 themes.
2 sets of composite icons, 1 for regular size and 1 for small.
Regular – 24x24px
Small – 16x16px
16×16 in 3 different states (normal, hover, disabled)
16×16 Search Icon for Seach Box/plugin (default hourglass)
16×16 icons (3 states) used to close sidebar and a tab.
Static : 16x16px
Busy : 16x16px animated gif
These icons appear in multiple places, including in bookmarks, history, and on tabs when no favicon is available for a site.
Bookmark Manager Toolbar*
Composite with various 24×24 icons
For when feeds are detected in a page
This should probably left as is, because it a universally recognised icon for feeds.
Background images can be put in various places, inclduing the sidebar, the
navigational toolbox (menubar, toolbars) and Options.