It’s generally the safest.
Have you created a new User? Try that (on both machines) and compare the results. If something works as expected in a new User account, but not in the existing account, then the problem is with your general configuration in the existing account.
Using the X11 session is still available, so no need to deal with the nvidia/wayland compatibility problems right now. Personally I’m waiting the explicit sync functionality which should arrive in Plasma 6.1 and in the nvidia driver so nvidia/wayland will work together much better.
I only use SVG icon themes.
And they work.
So despite your insistence … it is a problem local to you.
Are you sure your icon theme is complete and functional and up to date?
Actually - thats the upstream default for plasma.
But manjaro patched this to do the opposite.
So again there is something different about your setup for some reason.
The calculator does not work well.
Could you perhaps expand on that sufficiently to indicate just what the issue with the calculator appears to be? 
for example if you try to use the reziproke-function
4242 ^-1
and try to multiply the result with a second value
*24342
it results in an input error. this was working before but with the last update the Kcalc is simply broken.
Another one for the list, I suppose…
At least there are plenty of alternatives in the meantime; for example:
sudo pacman -S kalk
Plus a few (in AUR); Kalker; Numbat; Genius.
The following calculation does not work:
100.000 € (1+0,035 * 158 / 365) gives “Ein.gabefehler” = input error.
Up to now I updated 4 systems:
asus vivobook with ryzen: some minor problems due to update from active kde session. The following problems I reported on another thread were caused by some not-up-to-date supporting scripts for the flip-over display and the numpad simulation on the trackpad. Jetbrains Toolbox used to consume on CPU Core but that’s also fixed. Now running without problems with Plasma6 and wayland.
very old asus i5 Notebook: no problems at all, now on Plasma6 with wayland
zotac zbox ci-642nano: no problems at all, now on Plasma6 with wayland
Main Work-Desktop, Dell XPS8900 i7 + Nvidia RTX A4000, dual display with one in landscape and one in portrait mode: no problems at all, now running on Plasma6 with X11
As I like the window effects I’ve set quite a few of them on and don’t notice any slowdown.
The sound volume is reduced with any cause to 81 %.
KCalc input error is because it doesn’t chain results any more. E.g. 9, =, x, 9, = → Input error
That was an unbelievably stupid change, to make it behave like no other calculator in the world ever, you do wonder what some of these devs are smoking. It looks like it is getting fixed though.
Apart from the small (and usual) bugs, KDE 6 is much better than KDE 5.
Don’t give them ideas or the next update will be
KCalc now uses Reverse Polish Notation
