Going to build Emacs from the git repository.
Found this and this resources that suggest to compile it with xwidgets for Ubuntu 16.04.
On my Ubuntu 14.04, did install the corresponding dependencies with apt-get, but still getting this configure error:
configure: error: xwidgets requested but WebKitGTK+ not found.
Though libgtk-3-dev and libwebkitgtk-3.0-dev are installed.
Any hints?