Unable to click 'connect' to connect to hidden network

Upgraded machine to 16.04beta2 XFCE last night and noticed a problem with the network connections management.

If I have previously browsed, selected and connected to a WiFi network it's properties are stored under 'edit connections'. In my environment (maybe computer specific or just too many ESSIDs available) networks do not show up in the browse list sometimes, I could use 'connect to hidden network' to force a previous connection to start.

Now, with latest 16.04beta, when I attempt to do this the 'connect' button is greyed out and does not operate.

NOTE: this a problem with the GUI (when requesting action), not with the actual part of making the WiFi connection.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: xfdesktop4 4.12.3-2ubuntu1
ProcVersionSignature: Ubuntu 4.4.0-15.31-generic 4.4.6
Uname: Linux 4.4.0-15-generic i686
ApportVersion: 2.20-0ubuntu3
Architecture: i386
CurrentDesktop: XFCE
Date: Tue Mar 29 11:53:56 2016
InstallationDate: Installed on 2016-03-29 (0 days ago)
InstallationMedia: Xubuntu 16.04 LTS "Xenial Xerus" - Beta i386 (20160323)
SourcePackage: xfdesktop4
UpgradeStatus: No upgrade log present (probably fresh install)