External monitors as "desktops"

[Martin Flöser]

Am Montag, 28. Februar 2022, 15:47:40 CET schrieb Aleix Pol:
> On Sun, Feb 27, 2022 at 4:42 PM Neal Gompa <ngompa13 at gmail.com> wrote:
> > On Fri, Feb 25, 2022 at 5:55 PM Joshua J. Kugler
> > 
> > <joshua at joshuakugler.com> wrote:
> > > On Monday, February 21, 2022 2:31:43 AM AKST Thomas Lübking wrote:
> > > > Am Mon, Feb 21, 2022 at 10:28:42AM +0200 schrieb Vlad Zahorodnii:
> > > > >On 2/18/22 22:28, Joshua J. Kugler wrote:
> > > > >>Is there a way in kwin/plasma to make an external monitor its own
> > > > >>"desktop?" That is, when you hit "ctrl-tab" to change desktops, that
> > > > >>monitor does not change its display?  Similar to the way Mac (can)
> > > > >>handles external displays.>
> > > > >
> > > > >At the moment, kwin does not support per monitor virtual desktops,
> > > > >but
> > > > >there was an attempt to fix that.
> > > > 
> > > > I major obstacle will be that this isn't covered by the NETWM spec and
> > > > you'll have issues reporting the current virtual desktop or treating
> > > > requests to move or move windows there.
> > > > So the implementation would probably have to exist aside that concept
> > > > and then is just some way to manage the mapping state of windows on
> > > > the
> > > > current (in doubt only) virtual desktop.
> > > 
> > > As much as I would like to see KDE implement this, I'd much rather the
> > 
> > spec
> > 
> > > amended  than KDE break the spec and break interoperability with other
> > 
> > apps
> > 
> > > and desktops.
> > > 
> > > Is there a ticket/proposal in front of the the Freedesktop group to add
> > > something like this? If not, how would one go about requesting?
> > 
> > Does NETWM apply in a Wayland world? It and ICCCM are built on X11
> > specific stuff, so I suspect we can mostly ignore it for KWin on
> > Wayland.
> 
> I imagine it would still affect for Xwayland clients (which is no small
> detail).

I don't think it's a problem for Xwayland client. The biggest concern I had in 
the past on X11 was that windows would not render correctly due to thinking 
that they are not on the current desktop (e.g. video players pausing 
automatically). In an XWayland setup we are basically always in a situation 
where a window cannot know whether it is currently visible or not and it 
doesn't create problems. Furthermore I have never heard of any problems in i3 
with this.

> 
> And yes, if this was ever implemented, it probably should be a wayland-only
> feature.

fully agree, that should be Wayland only.

Martin