‘mod_pagespeed’ is module of Apache which is nothing but plugin which is used for compressing the external code of JavaScript and CSS.  It also used to increase the page load time as it combines multiple external JavaScript file in one file so it reduces the http request. 
Steps to install the mod_pagespeed on EasyApache 4-
2. After that restart Apache  service using below command –

$>/etc/init.d/httpd restart

 

3. Now you will need to clone the script in your cPanel server by below command –/usr/local/cpanel/3rdparty/bin/git clone https://github.com/pagespeed/cpanel.git /tmp/pagespeed/

4. Now create Speed.pm.tar.gz –

$> cd /tmp/pagespeed/Easy
$> tar -zcvf Speed.pm.tar.gz pagespeed
$> mkdir -p /var/cpanel/easy/apache/custom_opt_mods/Cpanel/Easy
$> mv Speed.pm Speed.pm.tar.gz -t /var/cpanel/easy/apache/custom_opt_mods/Cpanel/Easy/
$> cd && rm -rf /tmp/pagespeed


5. For verifying it you can login to WHM >> EasyApache >> Search for mod_pagespeed option. 
All done! Smile
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