[Radiant] add_attachment is not defined

[Jonathan Métillon]

Hi, I just installed the page_attachments Extension following the new
tutorial at http://dev.radiantcms.org/radiant/wiki/InstallingPageAttachments

I froze Radiant to edge, updated everything, and restarted the web
server and processes.

When I open a page from the admin, I see the Attachments (0) message,
and on top of it, the + icon. When I click this icon, nothing happens
and I get this error message in Firefox console:

Error: add_attachment is not defined
Source File: http://radiant.externalisation.fr/admin/pages/edit/1#
Line: 1

Note that I emptied my Firefox cache.

Any clue what's happening? Some javascript file not correctly copied maybe?

Thanks!

J.