Re: F23 KDE stability issues

[Felix Miata]

I've not seen locking problems in a long time. One of the very first things I 
do after creating a new user login is to disable screen locking. When I need 
my screen locked, I shut the machine down.

IMO, Fedora is the simplest way to have the most recent KDE release, and thus 
an unlikely place to experience what I consider a "stable" KDE environment. 
I've found KDE less than stable most of the period since v4.0 replaced v3.5.

F23 was released with Plasma 5.4.2. Currently in updates is 5.6.4. That 
difference is a double-edged sword, bringing in needed fixes, along with new 
bugs.

You might want to give TDE a try, for stability along with a familiar feel:
https://wiki.trinitydesktop.org/FedoraInstall#For_Fedora_23_.28R14.0.3.29