User Agent String explained :
|  Thunderbird 3.1.10 | |
|---|---|
| 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 | 
| Windows | Platform | 
| U | Security values: 
 | 
| Windows NT 5.0 | Operating System:  Windows 2000 | 
| en | Language Tag, indicates the language for which the client had been localized (e.g. menus and buttons in the user interface) en =  English | 
| rv:1.9.2.17 | CVS Branch Tag The version of Gecko being used in the browser | 
| Gecko | Gecko engine inside | 
| 20110414 | Build Date: the date the browser was built | 
| Thunderbird | Name :  Thunderbird | 
| 3.1.10 | Thunderbird version | 
| Description: | E-mail and news client developed by the Mozilla Foundation | 
| First visit: | 2011.06.08 05:23 | 
| Last visit: | 2018.07.29 12:54 | 
| All Thunderbird user agent strings | |