Comment # 33 on bug 1185276 from Stakanov Schufter

rpm -q Mesa
Mesa-21.2.4-292.1.x86_64

And confirmed it segfaults with SD channels. 
That said, the rpm -q Mesa
Mesa-21.1.6-8.21.x86_64
as for the bug 1189735 concerning segfault, this one is hit by another
dysfunction and hits e.g. also vidcutter (only showing green blurred images in
the preview). 

So video output is haunted by flicker, blockpixelview, inefficient or
impossible video editing since quite some time. The issue handled with 1189735
is just the try to restore normal operation with the hauppauge hardware for
what is simultaneous function of SD and HD channels with a quite common diseq
as it was since years. 

This one as opposed, we are talking about, I doubt it will be helped by it. 
Naturally, if the fixes would have had effect, I could not see it, because
Kaffeine is segfaulting too fast (and without debugger output since the very
beginning). So, the very use of SD channels crashes all already. No way to tell
you if this bug is in any way helped by the changes. May be, may not be. I
would concentrate on the segfault so that then we can go on with this one (if
it turns out to be still necessary of course).