Tour of /usr/local/mozilla

• chrome: the jar files containing the chrome (menus, buttons and window dressings) for the application.
  
• components: libraries implementing all the components currently installed.
  
• defaults: Lots of default values, including the default prefs files.
  
• icons: suggested desktop icons for the application.
  
• mozilla vs. mozilla-bin vs. run-mozilla.sh
  
• lib*.so: libraries implementing the core parts of Mozilla.
  
• plugins: system-installed plugins.
  
• regchrome, registry, regxpcom
• res: contains the default CSS, icons and XBL key bindings, plus dtds, entity lists and fonts for special dialects like mathml.
  
• searchplugins: some search engines that Mozilla knows about.