follow the below acl rule for block particular browser for squid user.

# vim /etc/squid/squid.conf
acl test src 192.168.7.218 192.168.7.222
acl browser_block browser Firefox
http_access deny test browser_block
http_access allow test

I love visiting sites in my free time. I have visited many sites but did not find any site more efficient than yours. Thanks for the nudge