this is going to be long...

i have a three full hd monitor setup, each one next to the other. one operates with the build in intel graphics adapter (hdmi) and the other two with a radeon graphics card (hdmi & dvi).

after the update to plasma (or whatever name you came up with recently) 5.6.4, i had the same output on each screen. after resetting the 'Display Configuration in the system settings (which worked), and a subsequent logout-login, the settings were gone and everything was like before (three displays with the same content).

after some digging (thanks for the wasted morning!), i found the following:

this happens only, if the kscreen background service is running:
in this case a file (~/.local/share/kscreen/1234567890abcdef...) which seems to contain the configuration, is constantly overwritten with a 'default' one [1], but what i want to have is, what i can configure [2], but is constantly overwritten after each login.

if kscreen background service is not running:
the configuration file is left untouched. but in this case only the two displays connected to the graphics card show the desktop (side by side, as it should be). the other one is ignored by kde/plasma/whatever.


[1]
'default' configuration file:
[
    {
        "enabled": true,
        "id": "fe5710f600023a7bebce11ba3d1c185d",
        "metadata": {
            "fullname": "xrandr-HP 23xi-xxxxxxxxxx",
            "name": "HDMI1"
        },
        "mode": {
            "refresh": 60,
            "size": {
                "height": 1080,
                "width": 1920
            }
        },
        "pos": {
            "x": 0,
            "y": 0
        },
        "primary": true,
        "rotation": 1
    },
    {
        "enabled": true,
        "id": "fad417046aa0f242b28c7fae518141c9",
        "metadata": {
            "fullname": "xrandr-HP 23xi-yyyyyyyyyy",
            "name": "HDMI-1"
        },
        "mode": {
            "refresh": 60,
            "size": {
                "height": 1080,
                "width": 1920
            }
        },
        "pos": {
            "x": 0,
            "y": 0
        },
        "primary": false,
        "rotation": 1
    },
    {
        "enabled": true,
        "id": "abead1c022dad8f54846b30ec554f307",
        "metadata": {
            "fullname": "xrandr-HP 23xi-zzzzzzzzzz",
            "name": "DVI-0"
        },
        "mode": {
            "refresh": 60,
            "size": {
                "height": 1080,
                "width": 1920
            }
        },
        "pos": {
            "x": 0,
            "y": 0
        },
        "primary": false,
        "rotation": 1
    }
]

[2]
the configuration file as it should be, and as it is after configuring the displays in system settings:
[
    {
        "enabled": true,
        "id": "fe5710f600023a7bebce11ba3d1c185d",
        "metadata": {
            "fullname": "xrandr-HP 23xi-xxxxxxxxxx",
            "name": "HDMI1"
        },
        "mode": {
            "refresh": 60,
            "size": {
                "height": 1080,
                "width": 1920
            }
        },
        "pos": {
            "x": 0,
            "y": 0
        },
        "primary": false,
        "rotation": 1
    },
    {
        "enabled": true,
        "id": "fad417046aa0f242b28c7fae518141c9",
        "metadata": {
            "fullname": "xrandr-HP 23xi-yyyyyyyyyy",
            "name": "HDMI-1"
        },
        "mode": {
            "refresh": 60,
            "size": {
                "height": 1080,
                "width": 1920
            }
        },
        "pos": {
            "x": 1920,
            "y": 0
        },
        "primary": true,
        "rotation": 1
    },
    {
        "enabled": true,
        "id": "abead1c022dad8f54846b30ec554f307",
        "metadata": {
            "fullname": "xrandr-HP 23xi-zzzzzzzzzz",
            "name": "DVI-0"
        },
        "mode": {
            "refresh": 60,
            "size": {
                "height": 1080,
                "width": 1920
            }
        },
        "pos": {
            "x": 3480,
            "y": 0
        },
        "primary": false,
        "rotation": 1
    }
]


Reproducible: Always

Steps to Reproduce:
1. konfigure displays
2. logoff
3. logon

Actual Results:  
each display shows the same content

Expected Results:  
displays should share desktop side by side