User Agent String explained :
|  Firefox 3.5.8 | |
|---|---|
| Mozilla | MozillaProductSlice. Claims to be a Mozilla based user agent, which is only true for Gecko browsers like Firefox and Netscape. For all other user agents it means 'Mozilla-compatible'. In modern browsers, this is only used for historical reasons. It has no real meaning anymore | 
| 5.0 | Mozilla version | 
| X11 | X Window System a windowing system for bitmap displays | 
| U | Security values: 
 | 
| Linux i686 | Operating System:  Linux running on a Intel Pentium Pro CPU | 
| de | Language Tag, indicates the language for which the client had been localized (e.g. menus and buttons in the user interface) de =  German | 
| rv:1.9.1.8 | CVS Branch Tag The version of Gecko being used in the browser | 
| Gecko | Gecko engine inside | 
| 20100202 | Build Date: the date the browser was built | 
| Firefox | Name :  Firefox | 
| 3.5.8 | Firefox version | 
| First visit: | 2010.03.07 12:33 | 
| Last visit: | 2025.07.23 09:25 | 
| All Firefox user agent strings | |