Until a few days ago, the graphics were working without problems in my laptop
(system info bellow). After the last update that changed (if I remember right)
some mesa libraries, screen rendering started to go in "jumps" with a lot of
tearing and rendering artifacts. 

3D applications are now slow. For example, until last week supertuxkart worked
without problems, but now it's impossible to use. 

Many desktop effects are not working anymore. For example, transparency when
dragging windows is not working or even available on Plasma desktop effect
settings, but expos������ effect, highlighting panels and blurring on log-out still
work (a few checkboxes where neither checked nor unchecked, they showed three
dots instead). Everything worked without problems before the update.

System information:

TUXEDO-Book-BC1507. 

Graphics (as reported by YaST2 hardware information): intel CoffeeLake-H GT2
(UHD Graphics 630). 

Copied from KInfoCenter:

Operating System: openSUSE Leap 15.4
KDE Plasma Version: 5.24.4
KDE Frameworks Version: 5.90.0
Qt Version: 5.15.2
Kernel Version: 5.14.21-150400.24.18-default (64-bit)
Graphics Platform: X11
Processors: 8 ������ Intel������ Core��������� i5-8300H CPU @ 2.30GHz
Memory: 15.4 GiB of RAM
Graphics Processor: llvmpipe 

The puzzling bit is "llvmpipe". I cannot find anymore an option to set the
graphic motor under Plasma's system settings ��������� Screen ��������� Compositor.

Bellow the output of

~> sudo lspci -v -s 00:02.0
00:02.0 VGA compatible controller: Intel Corporation CoffeeLake-H GT2 [UHD
Graphics 630] (prog-if 00 [VGA controller])
        Subsystem: CLEVO/KAPOK Computer Device 8555
        Flags: bus master, fast devsel, latency 0, IRQ 128
        Memory at 8d000000 (64-bit, non-prefetchable) [size=16M]
        Memory at 90000000 (64-bit, prefetchable) [size=256M]
        I/O ports at 4000 [size=64]
        [virtual] Expansion ROM at 000c0000 [disabled] [size=128K]
        Capabilities: [40] Vendor Specific Information: Len=0c <?>
        Capabilities: [70] Express Root Complex Integrated Endpoint, MSI 00
        Capabilities: [ac] MSI: Enable+ Count=1/1 Maskable- 64bit-
        Capabilities: [d0] Power Management version 2
        Capabilities: [100] Process Address Space ID (PASID)
        Capabilities: [200] Address Translation Service (ATS)
        Capabilities: [300] Page Request Interface (PRI)
        Kernel driver in use: i915
        Kernel modules: i915