KDE5 After resume from suspend I have corrupted labels under icons

I'm using KDE neon distribution (Ubuntu 16.04 LTS + latest KDE5 DE).

Suspend+resume looks to be mostly working on my notebook, but the labels under icons (I have "folder view" set up as background in plasma shell) are corrupted, like this:

On the left side corrupted icon, on the right fixed by dragging the icon few pixels and letting it drop back to its original place.

Looks to me, as it may be not graphics driver issue, but even KDE5 plasma folder view caching bug?

QUESTION:

• how to refresh the whole desktop easily? The KDE menu "Refresh Desktop" does not help (I guess there's some cache for icons, and it is not invalidated).

• how to create some high quality bug report, what kind of logs/commands output is worth of it, and where even to start to hunt down this one.

While I'm programmer myself, I don't do any Qt/KDE5 development, so I don't have even idea, which part of KDE is responsible for these, where to look for errors and which tools are available for diagnostics. A quick look into dmesg and /var/log/Xorg.0.log didn't bring up anything suspicious.

lshw -c video

  *-display               
       description: 3D controller
       product: GM107M [GeForce GTX 960M]
       vendor: NVIDIA Corporation
       physical id: 0
       bus info: pci@0000:01:00.0
       version: a2
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress bus_master cap_list rom
       configuration: driver=nvidia latency=0
       resources: irq:130 memory:de000000-deffffff memory:c0000000-cfffffff memory:d0000000-d1ffffff ioport:e000(size=128) memory:df000000-df07ffff
  *-display
       description: VGA compatible controller
       product: Intel Corporation
       vendor: Intel Corporation
       physical id: 2
       bus info: pci@0000:00:02.0
       version: 06
       width: 64 bits
       clock: 33MHz
       capabilities: pciexpress msi pm vga_controller bus_master cap_list rom
       configuration: driver=i915_bpo latency=0
       resources: irq:125 memory:dd000000-ddffffff memory:b0000000-bfffffff ioport:f000(size=64)

glxinfo | grep OpenGL

OpenGL vendor string: NVIDIA Corporation
OpenGL renderer string: GeForce GTX 960M/PCIe/SSE2
OpenGL core profile version string: 4.5.0 NVIDIA 375.66
OpenGL core profile shading language version string: 4.50 NVIDIA
OpenGL core profile context flags: (none)
OpenGL core profile profile mask: core profile
OpenGL core profile extensions:
OpenGL version string: 4.5.0 NVIDIA 375.66
OpenGL shading language version string: 4.50 NVIDIA
OpenGL context flags: (none)
OpenGL profile mask: (none)
OpenGL extensions:
OpenGL ES profile version string: OpenGL ES 3.2 NVIDIA 375.66
OpenGL ES profile shading language version string: OpenGL ES GLSL ES 3.20
OpenGL ES profile extensions: