.htaccess Redirect url with query string - .htaccess

Question

my website url : http://example.com/site
I want all links that have the word "tag" to be redirected along with their value.
for ex : http://example.com/site/tag/123453233445 redirect to => http://example.com/site/index.php?option=com_man&t=123453233445
my htaccess file : https://pastebin.pl/view/187c4dd9
complete htaccess file:
##
# #package Joomla
# #copyright Copyright (C) 2005 - 2020 Open Source Matters. All rights reserved.
# #license GNU General Public License version 2 or later; see LICENSE.txt
##
##
# READ THIS COMPLETELY IF YOU CHOOSE TO USE THIS FILE!
#
# The line 'Options +FollowSymLinks' may cause problems with some server configurations.
# It is required for the use of Apache mod_rewrite, but it may have already been set by
# your server administrator in a way that disallows changing it in this .htaccess file.
# If using it causes your site to produce an error, comment it out (add # to the
# beginning of the line), reload your site in your browser and test your sef urls. If
# they work, then it has been set by your server administrator and you do not need to
# set it here.
##
## No directory listings
<IfModule autoindex>
IndexIgnore *
</IfModule>
## Suppress mime type detection in browsers for unknown types
<IfModule mod_headers.c>
Header always set X-Content-Type-Options "nosniff"
</IfModule>
## Can be commented out if causes errors, see notes above.
Options +FollowSymlinks
Options -Indexes
## Mod_rewrite in use.
RewriteEngine On
## Begin - Rewrite rules to block out some common exploits.
# If you experience problems on your site then comment out the operations listed
# below by adding a # to the beginning of the line.
# This attempts to block the most common type of exploit `attempts` on Joomla!
#
# Block any script trying to base64_encode data within the URL.
RewriteCond %{QUERY_STRING} base64_encode[^(]*\([^)]*\) [OR]
# Block any script that includes a <script> tag in URL.
RewriteCond %{QUERY_STRING} (<|%3C)([^s]*s)+cript.*(>|%3E) [NC,OR]
# Block any script trying to set a PHP GLOBALS variable via URL.
RewriteCond %{QUERY_STRING} GLOBALS(=|\[|\%[0-9A-Z]{0,2}) [OR]
# Block any script trying to modify a _REQUEST variable via URL.
RewriteCond %{QUERY_STRING} _REQUEST(=|\[|\%[0-9A-Z]{0,2})
# Return 403 Forbidden header and show the content of the root home page
RewriteRule .* index.php [F]
#
## End - Rewrite rules to block out some common exploits.
## Begin - Custom redirects
#
# If you need to redirect some pages, or set a canonical non-www to
# www redirect (or vice versa), place that code here. Ensure those
# redirects use the correct RewriteRule syntax and the [R=301,L] flags.
#
## End - Custom redirects
##
# Uncomment the following line if your webserver's URL
# is not directly related to physical file paths.
# Update Your Joomla! Directory (just / for root).
##
# RewriteBase /
## Begin - Joomla! core SEF Section.
#
RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]
#
# If the requested path and file is not /index.php and the request
# has not already been internally rewritten to the index.php script
RewriteCond %{REQUEST_URI} !^/index\.php
# and the requested path and file doesn't directly match a physical file
RewriteCond %{REQUEST_FILENAME} !-f
# and the requested path and file doesn't directly match a physical folder
RewriteCond %{REQUEST_FILENAME} !-d
# internally rewrite the request to the index.php script
RewriteRule .* index.php [L]
#
## End - Joomla! core SEF Section.
Without comments htaccess file:
RewriteEngine On
RewriteCond %{QUERY_STRING} base64_encode[^(]*\([^)]*\) [OR]
RewriteCond %{QUERY_STRING} (<|%3C)([^s]*s)+cript.*(>|%3E) [NC,OR]
RewriteCond %{QUERY_STRING} GLOBALS(=|\[|\%[0-9A-Z]{0,2}) [OR]
RewriteCond %{QUERY_STRING} _REQUEST(=|\[|\%[0-9A-Z]{0,2})
RewriteRule .* index.php [F]
RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]
RewriteCond %{REQUEST_URI} !^/index\.php
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule .* index.php [L]

Answer 1

With your shown samples, could you please try following. Please make sure you clear your Browser cache before testing your URLs. Added rules from OP's provided rule file too here.
RewriteEngine On
##Newly entered rule by me here.....
RewriteCond %{REQUEST_URI} ^/(site)/tag/([0-9]+)/?$ [NC]
RewriteRule ^(.*)$ index.php?option=com_man&t=%2 [L]
##Op's written rule.
RewriteCond %{QUERY_STRING} base64_encode[^(]*\([^)]*\) [OR]
RewriteCond %{QUERY_STRING} (<|%3C)([^s]*s)+cript.*(>|%3E) [NC,OR]
RewriteCond %{QUERY_STRING} GLOBALS(=|\[|\%[0-9A-Z]{0,2}) [OR]
RewriteCond %{QUERY_STRING} _REQUEST(=|\[|\%[0-9A-Z]{0,2})
RewriteCond %{REQUEST_URI} !index\.php/?$ [NC]
RewriteRule .* index.php [F]
##Op's written rule.
RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]
##Op's written rule.
RewriteCond %{ENV:REDIRECT_STATUS} ^$
RewriteCond %{REQUEST_URI} !index\.php/?$ [NC]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule .* index.php [L]