Just an FYI, the state of “copy to clipboard” has changed - this “might” be useful to improve this feature.
There has recently been support added for execCommand('copy') to Chrome 43+ and upcoming support for Firefox 41 - couple that with existing IE10+ and Opera 29+ that actually seems like “good” browser coverage is coming.
I’ve added a StackOverflow answer to reflect this here with additional reference links and an example: