For more information, please visit the following pages:

• Firefox
• Mozilla Foundation
• Gecko

Latest user agents (if you are looking for complete list, download it here):

• Mozilla/5.0 (Macintosh; Intel Mac OS X x.y; rv:42.0) Gecko/20100101 Firefox/42.0 (en-GB)
• Mozilla/5.0 (Windows NT 6.1; rv:42.0; WUID=291ddec49e0c80af75673a29dda3bfbe; WTB=6533) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Macintosh; Intel Mac OS X 10.0; rv:42.0) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Macintosh; Intel Mac OS X 11_7_8; rv:42.0) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 10.0; WOW64; rv:42.0; WUID=921282dd7eacf3c7861953cd00b76af3; WTB=6533) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.1; http://temnos.com; rv:42.0) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.1; WOW64;) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.1; WOW64; rv:42.0; WUID=5d2f25739d3c60debf059fe3546f425d; WTB=21055) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.1; WOW64; rv:42.0; WUID=4742986139b954b8ac086688be8235cb; WTB=6787; WUID=aa23bf30500d8f63f6d116c246f5683a; WTB=21824) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (X11; Linux x86_64) Gecko/20100101 Firefox/42.0.2
• Mozilla/5.0 (Windows NT 5.1; rv:42.0; WUID=6f616ea3fa968fe8dbc4d3096abcdc37; WTB=8086) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.1; rv:42.0; WUID=fa552cbc478931831264c3eb8e8ae73b; WTB=3830) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.1; WOW64; rv:42.0; WUID=3257d1d81533f45831384bfcdbbb0803; WTB=18477) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (X11; Linux x8664; rv:42.0) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Macintosh; Intel Mac OS X 1.0; rv:42.0) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.3; WOW64; rv:42.0; WUID=a3f624e8f2b210ea58255b3d4961e30c; WTB=6787) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 10.0; rv:42.0; WUID=9d7e5cfe2aae47ecca7763ea7267d810; WTB=3231) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Android 4.4.4; Tablet; rv:42.0) Gecko/42.0 Firefox/42.0
• Mozilla/5.0 (Android 4.1.1; Tablet; rv:42.0) Gecko/42.0 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.1; WOW64; rv:42.0; WUID=1b079571432c33b47c454c91a9df5e46; WTB=28267) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Android 7.0; Mobile; rv:42.0) Gecko/42.0 Firefox/42.0
• Mozilla/5.0 (Windows NT 10.0; WOW64; rv:42.0; WUID=62866cb7b6528b6f2258bbd1be20e9df; WTB=3772) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Android 4.4.3; Tablet; rv:42.0) Gecko/42.0 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.1; WOW64; rv:42.0; WUID=0db9ad6175d1c35b0017af90668e81a7; WTB=6787) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.1; rv:42.0; WUID=2305a8328073a61d24a5f8423d153dbf; WTB=29529) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (X11; Ubuntu; Linux armv7l; rv:42.0) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 5.1; rv:42.0; WUID=e8b4caacb47616943953045abef82698; WTB=29529) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Android 6.0; Tablet; rv:42.0) Gecko/42.0 Firefox/42.0
• Mozilla/5.0 (Android 4.1.2; Tablet; rv:42.0) Gecko/42.0 Firefox/42.0
• Mozilla/5.0 (Android 4.0.4; Mobile; rv:42.0) Gecko/42.0 Firefox/42.0
• Mozilla/5.0 (Android 4.1.2; Mobile; rv:42.0) Gecko/42.0 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.1; rv:42.0) Gecko/20100101 Firefox/42.0 WebMoney Advisor WebMoney Advisor
• Mozilla/5.0 (Android 5.0.1; Mobile; rv:42.0) Gecko/42.0 Firefox/42.0
• Mozilla/5.0 (Android 4.2.2; Tablet; rv:42.0) Gecko/42.0 Firefox/42.0
• Mozilla/5.0 (Windows NT 5.1; rv:42.0; WUID=05b0496795afc544e0bcff7de8295972; WTB=28267) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Android 5.1.1; Tablet; rv:42.0) Gecko/42.0 Firefox/42.0
• Mozilla/5.0 (Android 4.2.2; Mobile; rv:42.0) Gecko/42.0 Firefox/42.0
• Mozilla/5.0 (Android 4.3; Mobile; rv:42.0) Gecko/42.0 Firefox/42.0
• Mozilla/5.0 (Android 5.0; Mobile; rv:42.0) Gecko/42.0 Firefox/42.0
• Mozilla/5.0 (Windows NT 5.1; WOW64; rv:42.0) Gecko/20100101 Firefox/42.0 DT-Browser/DTB7.42.0.19_01
• Mozilla/5.0 (Windows NT 10.0; WOW64; rv:42.0) Gecko/20100101 Firefox/42.0 DT-Browser/DTB7.42.0.19_10
• Mozilla/5.0 (X11; Linux i686 on x86_64; rv:42.0) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (compatible; Macintosh/1.0; +Mozilla/5.0 (Macintosh; Intel Mac OS X x.y; rv:42.0) Gecko/20100101 Firefox/42.0)
• Mozilla/5.0 (Windows NT 5.1; rv:42.0; WUID=d3522fe8c4a1f8c940e42ae0777917e4; WTB=3874) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 5.1; rv:42.0; WUID=7d9a93063b9ae665508bd2168f2a01df; WTB=592) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.1; WOW64; rv:42.0; WUID=2f67e66e17678acd11051e3cffe4f2a1; WTB=3869) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 10.0; WOW64; rv:42.0) Gecko/20100101 Firefox/42.0 OWASMIME/4.0500
• Mozilla/5.0 (Macintosh; Intel Mac OS X; rv:42.0) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.3; WOW64; rv:42.0; WUID=2846569fa3f56325fd4e5518fc1c0346; WTB=20595) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.1; WOW64; rv:42.0; WUID=826e13ae4d755c468e5f07c0b631b1b2; WTB=3580) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 10.0; Win64; x64; WOW64; rv:41.0) Gecko/20100101 Firefox/42.0 (x86 de) Anonymisiert durch AlMiSoft Browser-Anonymisierer 39479202
• Mozilla/5.0 (Windows NT 6.1; WOW64; rv:42.0; WUID=c3d19a1c98039453915ecd77b18a53d5; WTB=6787; WUID=2c38d9b42a8bc9a416f43ff93d13ac2c; WTB=21824) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.1; rv:42.0; WUID=cad200489421809ecd435c8269ddaede; WTB=2937) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.1; WOW64; rv:42.0) Gecko/20100101 Firefox/42.0 DT-Browser/DTB7.42.0.19_01
• Mozilla/5.0 (Android 3.1; Tablet; rv:42.0.1) Gecko/42.0.1 Firefox/42.0.1
• Mozilla/5.0 (Windows NT 6.1; WOW64; rv:42.0; .NET CLR 3.5; ffco7) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Android 4.2.1; Tablet; rv:42.0) Gecko/42.0 Firefox/42.0
• Mozilla/5.0 (Windows NT 5.2; WOW64; rv:42.0) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.1; rv:42.0) Gecko/20100101 Firefox/42.0 AlexaToolbar/ptAjSA3f-2.2
• Mozilla/5.0 (Windows NT 6.0; rv:42.0; WUID=0f7430a4a22224400e2b1b4b258bd92f; WTB=21824) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.1; WOW64; rv:42.0; .NET CLR 4.0.30319; ffco7) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (X11; FreeBSD i386; rv:42.0) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.3; +http://a-panov.ru/; Win64; x64; rv:42.0) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.1; rv:42.0) Gecko/20100101 Firefox/42.0 AlexaToolbar/alxf-2.21
• Mozilla/5.0 (Windows NT 6.1; WOW64; rv:42.0; WUID=0bc1ddbc8cac3f3ee083c37b4968e3d1; WTB=29529) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.1; rv:42.0) Gecko/20100101 Firefox/42.0 AlexaToolbar/p05tCbzf-2.1
• Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:42.0) Gecko/20100101 Firefox/42.0 AlexaToolbar/alxf-2.21
• Mozilla/5.0 (Windows NT 6.1; rv:42.0) Gecko/20100101 Firefox/42.0 DT-Browser/DTB7.42.0.19_04
• Mozilla/5.0 (Windows NT 10.0; WOW64; rv:42.0) Gecko/20100101 Firefox/42.0 AlexaToolbar/alxf-2.21
• Mozilla/5.0 (Windows NT 6.3; WOW64; rv:42.0) Gecko/20100101 Firefox/42.0 BLNGBAR BLNGBAR BLNGBAR BLNGBAR BLNGBAR BLNGBAR BLNGBAR BLNGBAR
• Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:42.0) Gecko/20100101 Firefox/42.0,gzip(gfe)
• Mozilla/5.0 (Windows NT 6.0; rv:42.0) Gecko/20100101 Firefox/42.0 AlexaToolbar/alxf-2.21
• Mozilla/5.0 (Android; Tablet; rv:42.0) Gecko/42.0 Firefox/42.0
• Mozilla/5.0 (Windows NT 5.1; rv:42.0) Gecko/20100101 Firefox/42.0,gzip(gfe)
• Mozilla/5.0 (Windows NT 10.0; rv:42.0) Gecko/20100101 Firefox/42.0 AlexaToolbar/alxf-2.21
• Mozilla/5.0 (Windows NT 5.1; rv:42.0) Gecko/20100101 Firefox/42.0 AlexaToolbar/alxf-2.21
• Mozilla/5.0 (Windows NT 5.1; rv:42.0; WUID=8e7d1eaf046f8bf5ac2709b724ef239d; WTB=2938) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.3; WOW64; rv:42.0) Gecko/20100101 Firefox/42.0 AlexaToolbar/alxf-2.21
• Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:42.0) Gecko/20100101 Firefox/42.0 AlexaToolbar/alxf-2.21
• Mozilla/5.0 (Windows NT 6.1; WOW64; rv:42.0) Gecko/20100101 Firefox/42.0 AlexaToolbar/alxf-2.21
• Mozilla/5.0 (X11; NetBSD amd64; rv:42.0) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 5.1; WOW64; rv:42.0) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:42.0) Gecko/20100101 Firefox/42.0,gzip(gfe)
• Mozilla/5.0 (X11; Linux i686 on x86_64; rv:42.0) Gecko/20100101 Firefox/42.0 webissimo3/3.7.22 svn30377
• Mozilla/5.0 (Mobile; rv:42.0) Gecko/42.0 Firefox/42.0
• Mozilla/5.0 (X11; Linux x86_64; rv:42.0) Gecko/19700101 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.0; rv:42.0; WUID=e88bd7c271e33368fb0625457e4ed5eb; WTB=6533) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Android 4.4; Tablet; rv:42.0) Gecko/42.0 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.1; WOW64; rv:42.0) Gecko/20100101 Firefox/42.0 OWASMIME/4.0400
• Mozilla/5.0 (Windows NT 6.1; WOW64; rv:42.0; WUID=4d1ef8ae38e3585c0cda9df3c28a6485; WTB=6533) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 10.0; WOW64; rv:42.0) Gecko/20100101 Firefox/42.0 DT-Browser/DTB7.42.0.19_01
• Mozilla/5.0 (Windows NT 6.1; rv:42.0; WUID=83693ae764b70a86974f168623aa71aa; WTB=4003) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (X11; OpenBSD amd64; rv:42.0) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Windows NT 5.1; rv:42.0) Gecko/20100101 Firefox/42.0 DT-Browser/DTB7.42.0.19_01
• Mozilla/5.0 (Android 4.0.3; Tablet; rv:42.0) Gecko/42.0 Firefox/42.0
• Mozilla/5.0 (X11; Linux i686; rv:42.0) Gecko/20100101 Firefox/42.0 webissimo3/3.7.21 svn30136
• Mozilla/5.0 (Windows NT 10.0; WOW64; rv:42.0; WUID=5b2c98cee1d50b15ff86ed67ca6f027e; WTB=3625) Gecko/20100101 Firefox/42.0
• Mozilla/5.0 (Android; Mobile; rv:42.0) Gecko/42.0 Firefox/42.0
• Mozilla/5.0 (Windows NT 6.3; WOW64; rv:42.0) Gecko/20100101 Firefox/42.0 OWASMIME/4.0500
• Mozilla/5.0 (Macintosh; Intel Mac OS X 10.9; rv:42.0) Gecko/20100101 Firefox/42.0 AlexaToolbar/alxf-2.21