No copying, printing as well as opening developers tools.

It can prevents user from :

• Select
• Print
• Right click
• Crtl / Shift / Alt / F12
• Open Developers Tools (Including opening in a separate window)

You can use CSS if you don't run Javascript. But for safety, you should use this javascript and make your page only show when the Javscript is on.

Download or

<script type="text/javascript" src="https://netrvin.github.io/PageGuard.js/pageguard.min.js"></script>

var anticopy_id = PageGuard.anticopy();

You can use the following codes to allow user to copy again (Cannot clear the CSS):

clearInterval(anticopy_id);
document.oncontextmenu = null; 
document.oncopy = null;
document.onselectstart = null;
document.ondragstart = null;
document.oncopy = null;
document.onbeforecopy = null;
document.onkeydown = null;
window.onhelp = null;

Supported:

• Chrome (latest version : 66)
• Opera (latest version : 52)
• Firefox (latest version : 59) (If it opens in a separate window, it will only work when the user open the console)
• Others (Not tested)

It can only run one at the same time.

var detect_key = PageGuard.detectDevTools(function () {
	// Your codes will run when developers tools is opening
});

You can also use the following codes to stop detecting:

PageGuard.stopDetecting(detect_key);

Don't let user get the anticopy_id and the detect_key. You can write your codes like this:

(function () {
    // codes
})();

Download or

<link href="https://netrvin.github.io/PageGuard.js/anticopy.min.css" rel="stylesheet">

https://netrvin.github.io/PageGuard.js/example.html

https://github.com/sindresorhus/devtools-detect

https://stackoverflow.com/questions/7798748/find-out-whether-chrome-console-is-open