In main screen of systemsettings there are bad rendered lines (white and grey stripes) in the background. They are nearly invisible but can be seen when looked carefully.

There is a screenshot:
http://i.imgur.com/Jymfwcr.png

I tried disabling Compositor, Switching renderer to XRender.
Moving-resizing windows does not change shape/position of the lines.
At first I think that my laptop screen is dying but in 2 other laptops (one is nearly brand new) I see same results. Also taking a screenshot "does" show the ugly lines. 
Changing theme to Oxygen does not change anything.

Second idea is about Intel's drivers. I have Core-i series laptops so I have integrated graphics for primary GPU which uses i915 and xfree86-video-intel. I'm aware of Intel's drivers have issues or serious bugs in rendering.

Reproducible: Always

Steps to Reproduce:
Start systemsettings5.
Look carefully to background.



This happens since I've switched Plasma 5 and still exist in my 5.3.2 desktop. I'll update when I get the 5.4. My system details are below and can share with you more if you want.

Asus N56VZ
Core i7 3610QM CPU with 8G RAM
Intel HD4000 GPU
runs ArchLinux and Qt ver 5.5.0