Bug 379324

Created attachment 207568 [details]
icons-vanishing-on-the-right-xinerama-screen.png

See the “google earth” icon in the middle of the screenshot which
I marked with a red circle.

I have moved this to the border of the left and the right xinerama
screen. The part of the icon which is in the right xinerama screen
is invisible.

If one moves the icon completely into the right xinerama screen,
it’s completely invisible.

If one remembers its position, it can still be moved back using the
mouse, it is just invisible but behaves normally otherwise.  For
example, one can still start the program when clicking on the position
where the invisible icon is.

A workaround to get the icons back to the left xinerama screen:

    cd ~/Desktop
    touch ttt.desktop

Or:

    cd ~/Desktop
    mv Google-googleearth.desktop  bla.desktop
    mv bla.desktop Google-googleearth.desktop

This brings *all* icons back to the left xinerama screen to default
positions.

Well, actually not always.

I tried

   touch ttt.desktop

again and nothing happend this time. Then I tried

   touch b.desktop

(which I hadn’t used before) and some of the icons came back to the
left xinerama screen, but *not* all of them.  To get the still missing
icons back, I moved them to different names and back to the original
name.

Created attachment 207571 [details]
plasma-backtrace

All this moving icons back and forth was probably too much for the
poor plasma thingy, it just gave up and segfaulted.

Attached is the backtrace. Probably useless because of the lack
of debugging symbols. I’ll try install more debuginfo package
to get a better backtrace next time.

Installing the debuginfo package is a bit more difficult
than expected, see bug #379338.

Plasma applets also disappear if they are moved to the right
Xinerama/MergedFB screen.

The only way I know to move them back is to edit
~/.kde4/share/config/plasma-appletsrc.

Accidentally I found that plasma applets can be moved freely between
the two xinerama screens *if* they are added initially to the right
screen!

If they are added initially to the left screen, they disappear when
they are move to the right screen. But if they are added to the right
screen initially, they are visible when added and can be moved to the
left screen and back to the right screen without disappearing.

Created attachment 208260 [details]
garbage-bins.png

The screenshot shows the border of the left and the right
MergedFB/Xinerama screen (You can see the border clearly because the
background picture changes there).

The upper garbage bin in the screenshot has been added
initially to the right screen, then moved to the border.
It is fully visible.

The lower garbage bin in the screenshot has been added initially to
the left screen, then moved to the border. The part which is in the
right screen now is hidden.

The problem still exists in the latest packages from STABLE/Factory.

The problem still exists in the latest packages from STABLE/Factory.

Mike> If they are added initially to the left screen, they disappear when
Mike> they are move to the right screen. But if they are added to the right
Mike> screen initially, they are visible when added and can be moved to the
Mike> left screen and back to the right screen without disappearing.

This behaviour is sometimes inverted when restarting the KDE4 session,
i.e. icons which are initially added to the right screen disappear
when they are moved to the left screen. But icons which are initially
added to the left screen can be moved to the right screen and back
without disappearing.

The problem still exists in the latest packages from STABLE/Factory.

This is not happening in Factory anymore. I can drag an icon in folder view between the screens and release landing the icon on either desktop. 

Closing as fixed.