Squid regex

\.sex\.com
\.redtube\.com

I also recommend you to block this way to cover all the possibilities:

^http://.*\.*sex\.com/*.*
^http://.*\.*redtube\.com/*.*

Let me explain what are you telling to squid to do with this regex:

^ = this is the beginning of the url

http:// = is the protocol that is always required

. = anything, for example, can be a subdomain or a www

* = the expression BEFORE (the subdomain or www) can happen or not

\ = the next char is not "anything" but a real dot

. = the real dot...

* = ...that can happen or not

sex = the domain

. = next char is a real real dot again

com = top level domain

/* = a dash that can happen or not (covering all the possible websites configurations here)

.* = anything can happen or not after the last dash (/index.php, blah blah)

Fix squid password prompt

To fix squid authentication we need set permissions in  /var/lib/samba/winbindd_privileged folder:

Set user root and group for winbind:

chown root:proxy /var/lib/samba/winbindd_privileged -R
or
chown root:squid /var/lib/samba/winbindd_privileged -R

Set folder permission
chmod 750 /var/lib/samba/winbindd_privileged -R

and restart winbind and squid

systemctl restart winbind

systemctl restart squid

Hide Squid info

Add at the end of error pages

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<hr noshade size=1>
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