Thread:User talk:Nischayn22/CopyToClipboard makes a strange blue line in explorer./reply (4)

No, it won't make your website any slower. I suggest you try to make a new extension of this, only editing a line in CopyToClipboard won't be enough. You have to load the JS library too. Have a look at http://www.mediawiki.org/wiki/How_to_become_a_MediaWiki_hacker/Extension_Writing_Tutorial to see how this is to be done.