I've recently installed Ubuntu 16.04 Beta on my system, because I need a lot of newer packages for development.
Eclipse has been very very difficult though. I've worked with Eclipse Mars on 14.04 and didn't notice any issues. Here, it started with installation, or at least at the time I thought my problems were due to installing Eclipse manually to /opt. I've since used the installer and the default settings.
In Eclipse, there are plenty of GUI glitches:
The entries in the Menubar menus were grayed out, until hovering with the mouse (e.g., Window ->)
The Window->Preferences Dialog doesn't appear, or only appears after several seconds.
Selecting the sub-menus in the Preferences Dialog doesn't display those pages (stays at "General").
CPU Util seems quite high.
Deleting a Project hung Eclipse with 100% CPU Util and I had to kill it (and delete .workspace)
i.e., unusable
Not sure if it's about OpenJDK8, or maybe a GTK3 related problem (since most of the bugs are graphical)? Anyone else having those issues?