If I click in "Anexo:" ( in portuguese ) , system shows error message
see attached images
It seems to be working correctly for me. That is dropzone widget, make sure you have your changesets applied, the dropzone.js library loaded and clear cache,
for me, if i click at button works too
( at left of screen, below a subject .... )
only occurs this problem, if I click in word "Anexo:" ( hyperlink )
For you worked in both way?
Browser issues ..
Chrome - OK
Firefox - NOK