Address Bar search fails for many duckduckgo bang! searches

Try the following in the address bar search in epiphany/Web (on Mint 17 
at least).

!amazon Hamlet
!gt podemos

Epiphany will just remain on the same page and not give any search 
results from duckduckgo, whereas if these queries are entered into
the duckduckgo input on the main page, duckduckgo.com, it works.

This assumes that the address bar search feature has been set-up for 
duckduckgo, ie, using the dconf-editor on the setting:
              org.gnome.Epiphany keyword-search-url
to value:
              https://duckduckgo.com/html/?q=%s

many regards,
T.