title: Which files are updated when upgrading joomla?
body: <p>I've been looking for the answer to this for ages now! Basically,I'm wondering which files will be changed when the joomla version is upgraded, i.e. what happens to any custom code- css, etc? Is it deleted and then has to be reimported by the admin from a backup, or does joomla preserve all this, and if so , which are the actual files it targets when doing the upgrade? Thanks in advance if anyone can help!</p>