Now that Ubuntu GNOME 16.04 (Xenial Xerus) is out, you may want to install the latest GNOME 3.20. I won't get into details about what's new in GNOME 3.20 since I've already covered that.
Ubuntu GNOME 16.04 uses GNOME 3.18 for the most part: GTK 3.18, along with GNOME Shell 3.18, GDM 3.18 and the 3.18.x release for most GNOME applications. Exceptions are Nautilus (3.14), GNOME Software and GNOME Calendar (both updated to version 3.20.x).
To upgrade to GNOME 3.20 in Ubuntu GNOME 16.04, you'll have to use the GNOME 3 Staging PPA.
The PPA doesn't have the complete GNOME 3.20 though. On a first look, I can tell you that the following packages weren't updated to version 3.20 in the PPA: Bijiben, Cheese, Epiphany, Evince, Boxes, Disks and probably others.
Nautilus (Files), Gedit, Maps, Documents, System Monitor, Terminal and so on, along with GTK+, Settings (Control Center / Settings Daemon), GNOME Shell, and GDM were all updated to version 3.20.
To see all the packages available for Ubuntu (GNOME) 16.04 in the GNOME 3 Staging PPA, click HERE.
I've been using GNOME 3.20 in Ubuntu GNOME 16.04 for a few hours and I didn't encounter any major issues however, there might be things I didn't notice. Furthermore, bugs can be introduced with future updates, especially since the PPA packages are not as widely tested as the packages available in the official Ubuntu repositories.
So use the PPA with care and only if you know what you're doing!
So use the PPA with care and only if you know what you're doing!
Update: pierremichaud points out in a comment below that the GNOME Calendar and Evolution calendar synchronization with Google doesn't work for now.
If something doesn't work the way it's supposed to or you simply don't want to use GNOME 3.20 any more, you can purge the PPA and go back to the default GNOME version (3.18) available in Ubuntu GNOME 16.04. You'll find instructions for how to do this at the end of the article.
How to upgrade to GNOME 3.20 in Ubuntu GNOME 16.04 (Xenial Xerus)
Before proceeding, it's important to mention that you should only use this PPA in Ubuntu GNOME. In Unity for instance, updating GTK and other libraries, along with applications without Unity patches can result in quite a bad desktop experience, crashes, etc.
Also, I recommend switching to the default GNOME theme (Adwaita), to avoid any issues that may occur with a newer GTK+ version and the theme you're using.
To add th GNOME 3 Staging PPA and upgrade to GNOME 3.20 in Ubuntu GNOME 16.04, use the following commands (read the important notice below before running the "dist-ugrade" command):
sudo add-apt-repository ppa:gnome3-team/gnome3-staging
sudo apt update
sudo apt dist-upgradeImportant! Read the output of "apt dist-upgrade" before entering 'Y' to make sure important packages won't be removed! This is up to you to figure out.
For instance, in my test, the "dist-upgrade" command displayed a message saying that "grilo-plugins-0.2-base" was about to be removed. I knew that's ok because "grilo-plugins-0.3-base" was mentioned below, in the section that lets you know about new packages that will be installed:
$ sudo apt dist-upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Done
The following packages will be REMOVED:
grilo-plugins-0.2-base grilo-plugins-0.2-extra libmutter0g
The following NEW packages will be installed:
gir1.2-geoclue-2.0 gir1.2-grilo-0.3 gir1.2-lokdocview-0.1 grilo-plugins-0.3
grilo-plugins-0.3-base grilo-plugins-0.3-extra libcamel-1.2-57 libgexiv2-2
libgrilo-0.3-0 libgspell-1-1 libjpeg62 libmutter0h libreoffice-gtk3
The following packages will be upgraded:
...................The same goes for "grilo-plugins-0.2-extra" and "libmutter0g". This is just an example though!
Once the upgrade is completed, it's best to restart your system to avoid running into issues.
How to revert the changes and go back to GNOME 3.18 in Ubuntu GNOME 16.04
If you want to revert the changes and go back to GNOME 3.18 in Ubuntu 16.04 (Xenial Xerus), you can purge the PPA. To purge the PPA, use the following commands:
sudo apt install ppa-purge
sudo ppa-purge ppa:gnome3-team/gnome3-staging
