It's expected that xclip doesn't work, since KWin intentionally doesn't update the X11 clipboard unless a X11 window is focused. You can use wl-paste --primary as a Wayland native alternative that acts as a clipboard manager to get privileged access.

(In reply to Zamundaaa from comment #1)
> It's expected that xclip doesn't work, since KWin intentionally doesn't
> update the X11 clipboard unless a X11 window is focused. You can use
> wl-paste --primary as a Wayland native alternative that acts as a clipboard
> manager to get privileged access.

Should I create a separate report for Emacs then? Emacs definitely has a focused window when I'm trying to make it access primary clipboard.

Is the focused window using X11 or Wayland? If it's Wayland native, it does need to be reported to emacs. If not, it should work

(In reply to Zamundaaa from comment #3)
> Is the focused window using X11 or Wayland? If it's Wayland native, it does
> need to be reported to emacs. If not, it should work

Just to clarify: by saying "focused window" you are talking about Emacs window, right?

So, my non-minimal actual problem (that involves a focused X11 window, i.e. Emacs) is: select text in Wayland Konsole, and then focus Emacs and make it fetch the primary selection. That doesn't work. So I should create a separate report for that, right?

I meant the Emacs window, yes.

FWIW I just tested this and it spits out the clipboard content... which is afaict expected, as you tell it to use the clipboard?
"xclip -o" prints the selection.
It does however only work if the selection is from a X11 window, it prints
> xclip: Error: There is no owner for the PRIMARY selection
when it's from a Wayland window. This might just be xclip being weird (as middle click paste works fine in Discord) but it might be a bug in KWin too

(In reply to Zamundaaa from comment #5)
> I meant the Emacs window, yes.
> 
> FWIW I just tested this and it spits out the clipboard content... which is
> afaict expected, as you tell it to use the clipboard?
> "xclip -o" prints the selection.
> It does however only work if the selection is from a X11 window, it prints
> > xclip: Error: There is no owner for the PRIMARY selection
> when it's from a Wayland window. This might just be xclip being weird (as
> middle click paste works fine in Discord) but it might be a bug in KWin too

I'm sorry for confusion.

Okay, so, should I maybe create a separate report (and have this one closed) that's using X11 Emacs specifically to fetch primary selection? I mean, from the discussion above it seems like an actual application with a window apparently might suit better.

Btw, I just found one peculiar thing with Emacs: `middle-click` paste into Emacs works no problem. What does not, however, is accessing primary selection programmatically by evaluating `(gui-get-selection 'PRIMARY)`.

I'd appreciate any code pointers I might have a look at it in my spare time

Can you confirm if emacs is a wayland window or not. 
An easy test is to run xprop and hover over the emacs window. If it changes to a + icon, it's in xwayland.

Emacs is an X11 window. There's an experimental Wayland support aka "pure GTK3", but AFAIK it has problems on X11 (which is why it was never made default), so I'd prefer to stick to X11 build because I might have to switch between Wayland and X11.

FTR, I just tested same way on Gnome Wayland and X11 Emacs does see selection from Wayland Konsole, so it is something on the kwin's side.

Oh, somehow I missed the previous notification. Yeah, all information has been provided, it's just that the status wasn't changed.

So per notification, changing to REPORTED