&quot;paste&quot; is not enabled for non-trusted scripts on FF 41+. 
A extensions&#x27; scripts can use &quot;paste&quot; since they are trusted scripts; but a webpage&#x27;s script cannot.<p>I believe that footnote is a doc error, since copy&#x2F;cut are enabled w&#x2F;o user.js override on FF 41+.<p>I don&#x27;t know if there is any current plans to make &quot;paste&quot; available for all scripts - I don&#x27;t think there would be because of the obvious concerns.