Plasma 5 keep crashing after IDLE

[xtralayer]

Hi,

My Plasma 5 keeps crashing after a few minutes of idle (about 10 minutes), I get the following in dmesg:

[ 8193.025615] kactivitymanage[5103]: segfault at 7f5d5d086c50 ip 00007f5d48077a91 sp 00007ffd95e34f48 error 4 in libQt5Sql.so.5.5.1[7f5d48062000+47000]
[ 8194.062581] nvidia-modeset: Freed GPU:0 (GPU-71d0d563-4083-5e38-6fb4-502c20dd4197) @ PCI:0000:01:00.0
[ 8214.122853] nvidia-modeset: Allocated GPU:0 (GPU-71d0d563-4083-5e38-6fb4-502c20dd4197) @ PCI:0000:01:00.0
[13428.664923] kactivitymanage[25521]: segfault at 7f14c6417c50 ip 00007f14a821ba91 sp 00007ffddf56f1c8 error 4 in libQt5Sql.so.5.5.1[7f14a8206000+47000]

I looked around and alot of people seem to be getting this and it may be related to xprotobuf but I'm not sure, I tried using downgrading that package and using both unstable and stable plasma 5 in portage but it still crashes if I'm away for a few minutes.

Thanks.

[xtralayer]

Well running startx alongside DISPLAY=:0 kwin_x11 & fixes it somehow...

[xtralayer]

It crashes now after turning the hdmi monitor on and off, the monitor is hooked to a gtx 980 ti (nvidia).
crash log: http://pastebin.com/RfLT4AZ2

UPDATE: seems to be an old bug from 2014 that still haven't been fixed: https://bugs.kde.org/show_bug.cgi?id=340267

I'll switch to another environment till this gets resolved.

[asturm]

There's good news in so far as I have tested a patch yesterday that fixes the issue for me. However it bumps the plasma-workspace requirement to Qt-5.6.0 and I wouldn't recommend upgrading to it before 5.6.1 is around.

[dmpogo]

I see this kactivitymanage crashes with Qt-5.6.1 still