Comment # 3 on bug 960480 from Wolfgang Bauer

You are talking about the actions that the device notifier provides, right?

Well, Kaffeine is a KDE4 application and KDE4 uses different filesystem
locations for those actions than Plasma5/KF5 does, so they don't show up in
Plasma5.
We could add a symlink/copy to the Kaffeine package, please file a new bug
report against Kaffeine so it won't get forgotten...

For Packman's VLC this has been fixed recently, the next Packman update at
least should also create actions for KF5.
I'm not sure it makes sense to release an official update for Leap 42.1 though,
as the included version is unable to play back most multimedia formats anyway.
Although for Audio CD's it might even be worth it... (but again, you should
probably file a new bug report against vlc)

For K3b it should work, AFAIK the openSUSE package does install the device
actions to KF5's place as well. If you are using the Packman version, you
should report it to them, their package is completely independent of
openSUSE's.