Even when "Hide Toolbars" is unchecked in fullscreen mode, my addon bar disappears. Any way to stop this?

Please try to save the customize setting, this may toggle the add on toolbar. There is a bar that pins add ons automatically. For example, my add ons next to my search and url bar are there. Go to Tools > Toolbar > Customize.. and you can remove the add on icons from this toolbar that will not hide :-)

I hope this helps.

Add code to the userChrome.css file below the default @namespace line.

• http://kb.mozillazine.org/userChrome.css

@namespace url("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"); /* only needed once */

#addon-bar[moz-collapsed="true"][collapsed="false"] { visibility:visible !important; }

The customization files userChrome.css (user interface) and userContent.css (websites) are located in the chrome folder in the Firefox profile folder.

• http://kb.mozillazine.org/Editing_configuration