To be able set RELEASE to "xfce-4.14" in ci/build_libs.sh, to allow testing backward compatibility with XFCE 4.14 container, libgtk2.0-dev package must be installed, which is required by XFCE 4.14.
Signed-off-by: Mateusz Gozdek mgozdekof@gmail.com
I wonder if 4.14 Docker tags could be also published or is 4.14 compatibility something we should even bother.