problems to quit KDE5
 

I have slackware64-current with AlienBob's Plasma5 installed.

Today something new appeared : when trying to quit KDE (as usual, with a right click on the screen, then "quit") the system takes a long time to ask a confirmation. But it finally can quit.

Something new also in "dmesg" :

[ 952.058638] traps: upowerd[18243] trap int3 ip:7f501007c855 sp:7ffcfd5501e0 error:0 in libglib-2.0.so.0.6200.4[7f5010044000+7d000]

Something else is new too : when quitting I have can only close the X session. In the past it was also possible to halt, reboot or hibernate.

Multilib system?

Yes, I have also multilib

As Z80 suggested in cwizardone post "After The Last Two Updates To Current There Are Network And Xorg Problems" , I went back to "polkit-0.116-x86_64-2" (instead of version 3), and reinstalled ConsoleKit2-1.2.1-x86_64-2, and the problem is solved.

I recently added a polkit-compat32 package, but the first version was broken as Pat Volkerding pointed out to me. I fixed that package but you may still have the broken version installed.
And then also re-install the Slackware polkit and ConsoleKit2 packages, either using "slackpkg reinstall" or by downloading these packages yourself and running "upgradepkg --reinstall" on them.

Sorry, I make a mistake, I went back to ConsoleKit2-1.2.1-x86_64-2 and reinstalled polkit-0.116-x86_64-2....

@Alien Bob, I installed the new polkit-compat32-0.116-x86_64-2compat32.txz package, and reinstalled polkit-0.116-x86_64-2, and also ConsoleKit2-1.2.1-x86_64-3, and everything works.

So it is not necessary to use a previous version of ConsoleKit2-1.2.1