This article describes why text you type in Firefox can get jumbled or reversed. For example, if you type "Firefox", the result is "xoferiF".

Java applets

Having a Java applet open on any page can cause this problem. An updated version of the Java plugin that fixes this problem is available for Firefox 3.

Print preview

This bug can occur when when a Print Preview window is opened by a page. Make sure that all Print Preview windows are closed before typing.