Board Thread:Support Requests - Getting Technical/@comment-11371204-20130629013522/@comment-4674838-20130629035050

It is impossible for you to change any security setting that would allow you to paste directly into the visual editor with the right-click -> paste button.

The "security setting" to which it is referring is the fact that JavaScript executing in a web browser does not have access to your clipboard. Which is a very good thing, because if it did, thousands of people would be having credit card numbers, passwords, addresses, etc. stolen from their clipboard on a daily basis.

That custom "paste" button you see in the visual editor is not a native feature of your web browser, it's actually a custom designed element of the webpage – and it requires JavaScript to function, so it can't access your clipboard.

Technical sidenote: Adobe flash, however, can access your clipboard, the ZeroClipboard library (and its various forks) being one commonly used artifact on certain websites that have custom copy/paste features. But Wikia does not use this library so far as I know.