Kubuntu 15.04 shows a notification (and a taskbar icon) on each boot, after the log in, offering me to install extra packages, specifically flash, and I really don't want to install it. I've pressed "cancel" many times, but in the next boot the notification will pop-up again.
What can I do to make the notification stop?
I found an answer to this on the Kubuntu forum.
In KDE you can turn off "Restricted codec availability" under
System Settings' ->
It works for me (Kubuntu 15.04 with kubuntu-ppa backports).