Can't install rpi-chromium-mods from pixel upgrade

Question

I have a Pi 2 that has been kept current with the latest Raspian. I am trying to install the Pixel update that was posted on the Raspberry Pi blog this morning. Here are the commands:

sudo apt-get update  
sudo apt-get dist-upgrade  
sudo apt-get install -y rpi-chromium-mods  
sudo apt-get install -y python-sense-emu python3-sense-emu  
sudo apt-get install -y python-sense-emu-doc realvnc-vnc-viewer

The first two commands appear to execute correctly. Line 3, installing the chromium piece, fails, as it cannot find rpi-chromium-mods.

Answer 1

On September 28, 2016, Simon Long presented in the official Rasperri Pi blog a beautification of the GUI for the Raspian distro (https://www.raspberrypi.org/blog/introducing-pixel/) called PIXEL (“Pi Improved Xwindows Environment, Lightweight”). He also explained how to update an existing Raspian Jessie installation:

sudo apt-get update
sudo apt-get dist-upgrade
sudo apt-get install -y rpi-chromium-mods
[...]

I followed the instructions exactly but got stuck at the 3rd statement:

$ sudo apt-get install -y rpi-chromium-mods
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to locate package rpi-chromium-mods

Thanks to Simon's support I could fix the problem by appending "ui" as component to all Apt lines found in /etc/apt/sources.list.d/raspi.list:

deb http://archive.raspberrypi.org/debian/ jessie main ui

After having edited the file, I resynchronized my repos ( sudo apt-get update ) and the rpi-chromium-mods package installed successfully ( sudo apt-get install -y rpi-chromium-mods ).