Upgrade KDE Plasma on Kubuntu 16.04.1

Remember that 16.04 was released in April, and the latest point release for it wasn't terribly recent. It would be pretty amazing if 16.04 shipped with a build of KDE that came out about a week ago. According to KDE's packages page, 16.04 actually came wih 5.5.3, so 16.04.1 must have upgraded to 5.5.5.

The page also says that Kubuntu can get Plasma 5.6.5 with Backports from the PPA. This isn't the latest version, but it appears that is the latest stable build for Ubuntu. I would recommend you install this one.

sudo add-apt-repository ppa:kubuntu-ppa/backports
sudo apt-get update
sudo apt-get upgrade

In case 5.6.5 isn't new enough, the Staging branch happens to have 5.7.2 for Xenial and Yakkety. You can try it out, but it isn't stable, so expect issues. I don't really recommend this, but if you want the latest you can easily get:

sudo add-apt-repository ppa:kubuntu-ppa/staging-plasma
sudo apt-get update
sudo apt-get upgrade

If you really, really, really want 5.7.4, you can build KDE completely from source. The code can be found here and build instructions here. There are quite a few packages to build, however, so I recommend you settle for 5.6.5 or 5.7.2. Unless you absolutely have to have 5.7.4 on Ubuntu, the effort needed for this is probably not worth the 0.0.2 point upgrade.

As for the reason there is no 5.7.4 on Ubuntu yet: well, take a look at the source; it's a lot. The Kubuntu team has to build all that for Ubuntu after the KDE team releases it, and make sure it's stable. Then they also have to wait for a new Ubuntu release (xx.04 or xx.10, not xx.xx.Y) to actually package it in by default.

Stable releases (5.6.5) can be found in the backports ppa. To install do:

sudo add-apt-repository ppa:kubuntu-ppa/backports -y && sudo apt-get update && sudo apt-get dist-upgrade

PLEASE BE EXTRA CAREFUL WITH THE EXPERIMENTAL PPA.

Experimental releases (5.7.2) can be found in the staging ppa. To install do::

sudo add-apt-repository ppa:kubuntu-ppa/staging-plasma -y && sudo apt-get update && sudo apt-get dist-upgrade