In KDE 5.4.2 in Kubuntu 15.10, we found that three options
(Actions, Compress, Extract) disappeared from context menu in
Dolphin. But actually these three options are there, are still usable. Probably
this is just a little error and we now can show them again
by this command:
sudo ln -s /usr/share/kde4/servicetypes/konqpopupmenuplugin.desktop /usr/share/kservicetypes5/
This command will give /usr/share/kservicetype5 directory a file named konqpopupmenuplugin.desktop (as a symbolic link) from /usr/share/kde4/servicetypes/ directory. By having this file, Dolphin will automatically recognize its own plugins for right-click context menu such as Compress Here, Extract Here, and much more. You don't need to restart to see the changes. See pictures below.
What you get by doing this simple workaround is what you can see in Dolphin Services List (menu Tools > Configure Dolphin > Services). Now, you have some additional plugins activated such as Compress:, Extract:, Send As Email:, and some more. We say thanks to Markus Straub for his comment about this fix in https://bugs.launchpad.net/ubuntu/+source/dolphin/+bug/1499530/comments/4.