I installed leap 15.4 on my new AMD 7700x computer - so far, so good. However, 
kaffeine is not working as expected.
When running a TV application (or playing a file ...) I can use it in a window
nearly half size of the screen (3840 x 2160). When zooming to larger sizes the
picture vanishes and I only see a black window - the frames are there, the
sound is output, but no more video.
In contrast I can do the very same using vlc without a problem (but not play tv
of course). Full screen is working there.
As kaffeine to my knowledge uses libvlc this sounds strange to me.
System setup:
AMD 7700x computer, 64 GByte ram, using onboard graphics of the CPU. Kernel: 
vmlinuz 6.1.5 from openSUSE repository (with the stock kernel graphics
resolution is inacceptable as the driver has apparently not been backported to
5.3.x ...)
This is very annoying.
The only logging information I get from kaffeine is 
libEGL warning: DRI2: failed to authenticate
when starting television. But libEGL is there and there is apparently nothing
wrong with the links ...
Any input is very much appreciated, I found nothing usable in the net.