The exact location of the fix will depend on what Joomla template you're using, but the change can be implemented in the css. Wherever your main or custom css file is located, simply add the following:

 

#turnkey-credit {

     display: none !important;

}

 

Hope this helps!

So unless you intend to use the substitute module for anything else, the easiest way to disable it is to disable that module:

a2dismod substitute && service apache2 reload

If you want to understand how we include the credit footer in the first place, have a look at the source code on GitHub.

Also I understand that there are many legitimate reasons why you may want to disable the credit footer, but remember that a lot of hard work goes into these appliances. We love to be able to provide these products to the community for free download, but the credit footer is essentially marketing for us. So if you do remove the footer it would be really awesome if you consider other ways in which you might be able to give something back. As a Joomla developer, giving feedback on any friction points and/or what might make the appliance better (or better still committing code to address these) would be super awesome! :)