Joomla is a content management system. By default joomla doesn’t come with any sort of content restriction policies. Although with user management you can apply content restriction but for anonymous users or your joomla website visitors, this is not possible.
One way to restrict content or source code copy from your website is to disable the right click. When you disable the mouse right click, a visitor wont be able to access the properties of the web page, which will secure that page.
With the JoomSimple Content Protection extension of Joomla you can disable right click as well as you can disable the CONTROL+C option for your website visitors. Here is how it works.
When you enable this plugin, it will ask you whether you want to disable just right click or you want to disable the text copying also. You can also configure this extension to restrict content for users that belong to a specific user group like administrators, authors, publishers or managers.
Here is a screenshot of this plugin, after I applied it to my Joomla site and tried to copy the content with CTRL + C shortcut, this is what I got -
