Fredy Neeser/Zurich/IBM wrote on 01.11.2016 20:33:36:
...


> I removed

>       ~/.config/plasmashellrc and
>       ~/.config/plasma-org.kde.plasma.desktop-appletsrc
>
> executed 'kquitapp5 plasmashell' from a konsole window,

> and then 'kstart5 plasmashell' to restart it.
> This resulted in clean (almost empty) desktop containments with
> fresh wallpapers (one on LVDS, the other on the external monitor)
> and one (default) panel placed on the primary display.
>
> After this cleanup, adding an application to Desktop creates

> an icon on each desktop containment. Application icons are
> consistent in size and nicely aligned; moreover, their position
> can be adjusted separately on each desktop containment.

I should add that this cleanup causes plasmashell to create
(default) desktop containments with
  Layout = Folder View
rather than
  Layout = Desktop
which I had before.

So the nice behavior with application icons can be attributed
to the Folder View layout (you can see the layout by right
clicking the desktop > Desktop Settings > Wallpaper).

Icons added to Folder View layout are visible on each screen;
they are not shown when you convert the layout to Desktop
but reappear when you go back to Folder View.

Icons added to Desktop layout are visible only on the screen
to which they are added; otoh, they are also shown when the
layout is switched to Folder View.

Somewhat inconsistent ... so it seems best to stick to
one layout ...

Cheers,

Fredy Neeser
IBM Research Zurich