Latest Firefox 53 user agents:

User Agent Platform Device
Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:53.0) Gecko/20100101 Firefox/53.0 Ubuntu Unknown
Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:21.0) Gecko/20130331 Firefox/53.0 Ubuntu Unknown
Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:53.0) Gecko/20100101 Firefox/53.0 [ip:87.166.92.211] Ubuntu Unknown
Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:53.0) Gecko/20100101 Firefox/53.0 [ip:87.166.80.213] Ubuntu Unknown
Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:53.0) Gecko/20100101 Firefox/53.0 [ip:79.251.99.157] Ubuntu Unknown
Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:53.0) Gecko/20100101 Firefox/53.0 [ip:79.251.107.222] Ubuntu Unknown
Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:53.0) Gecko/20100101 Firefox/53.0 [ip:79.251.105.138] Ubuntu Unknown
Mozilla/5.0 (X11; Ubuntu; Linux armv7l; rv:53.0) Gecko/20100101 Firefox/53.0 Ubuntu Unknown
Mozilla/5.0 (X11; U; SunOS sun4u; en-US; rv:1.8.1.12) Gecko/20080210 Firefox/53.0 Solaris Unknown
Mozilla/5.0 (X11; U; SunOS sun4u; en-US; rv:1.8.1) Gecko/20061024 Firefox/53.0 Solaris Unknown
Mozilla/5.0 (X11; U; SunOS sun4u; en-US; rv:1.7.8) Gecko/20050512 Firefox/53.0 Solaris Unknown
Mozilla/5.0 (X11; U; OpenBSD i386; de-DE; rv:1.8.1.6) Gecko/20080429 Firefox/53.0 OpenBSD Unknown
Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2) Gecko/20100305 Gentoo Firefox/53.0 Gentoo Unknown
Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.7.12) Gecko/20060202 CentOS/1.0.7-1.4.3.centos4 Firefox/53.0 CentOS 1 Unknown
Mozilla/5.0 (X11; U; Linux i686; pl-PL; rv:1.9.0.5) Gecko/2008121300 SUSE/3.0.5-0.1 Firefox/53.0 SUSE 3 Unknown
Mozilla/5.0 (X11; U; Linux i686; fr-be; rv:1.9.0.8) Gecko/2009073022 Ubuntu/9.04 (jaunty) Firefox/53.0 Ubuntu 9 Unknown
Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.0.9) Gecko/2009042113 Ubuntu/8.10 (intrepid) Firefox/53.0 Ubuntu 8 Unknown
Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.0.10) Gecko/2009042812 Gentoo Firefox/53.0 Gentoo Unknown
Mozilla/5.0 (X11; U; Linux Gentoo i686; pl; rv:1.8.0.8) Gecko/20061219 Firefox/53.0 Gentoo Unknown
Mozilla/5.0 (X11; Linux x86_64; rv:53.0.2) Gecko/20100101 Firefox/53.0.2 GNU/Linux Unknown