noveau + openGL: mouse pointer unstable in KDE

[jaegermeister]

Hello,
starting with recent kernels of 4.18.x series, I have a problem concerning the mouse pointer, as it can either disappear or flash and, when hovering windows, like for instance dolphin, it literally moves "squares" around the pointer.
This happens when composting with openGL 3.1 and 2.0 but NOT with Xrender, which, unfortunately, disables great part of the desktop effects I like to see.
This is my graphic card, always performed great with noveau:

Code Auswählen Erweitern

Graphics:  Device-1: NVIDIA GF106GL [Quadro 2000] driver: nouveau v: kernel
           Display: x11 server: X.Org 1.20.1 driver: modesetting unloaded: fbdev,vesa
           resolution: 1920x1080~60Hz, 1920x1080~60Hz
           OpenGL: renderer: NVC3 v: 4.3 Mesa 18.1.9
Is this due to noveau or to KDE implementation of openGL?How to solve it?THX

[piper]

Have you tried

In settings > desktop behavior - desktop effects - turn everything off -reboot

If that works, go back and enable things you want one at a time, "blur" is usually a problem for some people with older cards.

Have you tried another mouse ?

[jaegermeister]

Hi,
thanks for answering.
Tried both things, no effect. Mouse is ok, other mice behave the same.
Whenever I turn on openGL pointer starts disappearing/appearing.
Just run through a du (but kernel, as 4.19.0 crashed during boot, but that's another story) before writin OP and squares appear seldom, compared to recent scenarios. I don't know if the benefit was through 4.18.14 or recent KDE updates. But this problem is something which is not older than a month.

[piper]

I am not a fan of nouveau drivers

Have you tried the nvidia-legacy-390xx-driver ?

https://packages.debian.org/sid/nvidia-legacy-390xx-driver

[jaegermeister]

Actually, I used them till a couple of years ago, till when noveau became usable.

The more time lapses, the more unmantained proprietary drivers create incompatibilities with new kernels (eg: no modesetting and worse) and are becoming a "no way to go" option. Since I abandoned them the machine got smoother and less problematic.

[piper]

Each to their own I guess, 

I find quite the opposite