[O] [Show Org source] button does not work

[Kynn Jones]

The [Show Org source] button at the bottom of pages such as

http://orgmode.org/worg/

does not work.  Nothing happens when one clicks on it.  It's supposed
to execute the statement `show_org_source()`, but as far as I can
tell, the function `show_org_source` is not to be found in the page's
JS.

I've tried this in multiple browsers and OSS.

Best,

kj