Something I noticed after making my Flash click-to-activate a while back. That seems like a HUMONGOUS tunnel to create in order to allow copy to clipboard, and fairly irresponsible on GitHub's part.
What developer doesn't know how to copy to clipboard?
Github claims that the flash version is "currently the only reliable way to put data in the clipboard". This seems to indicate that they looked at the native browser option and found it unacceptable for their use case.
What developer doesn't know how to copy to clipboard?