Bug 464892 - Multi-monitor issues under X11 with NVIDIA GPU
Summary: Multi-monitor issues under X11 with NVIDIA GPU
Status: RESOLVED DUPLICATE of bug 462725
Alias: None
Product: kwin
Classification: Plasma
Component: multi-screen (show other bugs)
Version: 5.26.90
Platform: Debian testing Linux
: NOR normal
Target Milestone: ---
Assignee: KWin default assignee
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2023-01-27 10:17 UTC by Kenny Hui
Modified: 2023-03-04 09:56 UTC (History)
3 users (show)

See Also:
Latest Commit:
Version Fixed In: 5.27
kenny.mh.hui: Wayland-


Attachments
Plasma Panel and Start screen, with no icons appearing. Below is what seems like 1 entry in a context menu, taking up an entire monitor. (1.50 MB, image/png)
2023-01-27 10:17 UTC, Kenny Hui
Details
Display configuration in System Settings (95.87 KB, image/png)
2023-01-28 03:55 UTC, Kenny Hui
Details

Note You need to log in before you can comment on or make changes to this bug.
Description Kenny Hui 2023-01-27 10:17:30 UTC
Created attachment 155697 [details]
Plasma Panel and Start screen, with no icons appearing. Below is what seems like 1 entry in a context menu, taking up an entire monitor.

SUMMARY
Not sure where to start, but a chain of issues happens when a second monitor is connected and enabled, making plasma very unstable for general use.
In my case, my main GPU is an Intel HD 630 (Main monitor@1080p60) with an NVIDIA GPU (Connected to my second monitor@1080p60) in prime render offload mode.

STEPS TO REPRODUCE
1. Connect and enable the second monitor

OBSERVED RESULT
If second monitor connected & enabled on startup, no icon will appear in the panel, widgets and the desktop.

If the second monitor is connected/enabled mid-way, most existing icon will disappear once you hover/interact over them. (Some however still remains, for example task switcher)

Checking journalctl, I only noticed the following abnormality:
kwin_x11[1568]: kf.config.core: "\"NaturalSize_inf\" - conversion of \"-2147483648,-2147483648\" to QSizeF failed" (When Task Switcher is opened)

kwin_x11[1568]: qt.qpa.xcb: QXcbConnection: XCB error: 9 (BadDrawable), sequence: 35660, resource id: 8392691, major code: 14 (GetGeometry), minor code: 0

(Not sure how much relevancy this has)

Window title will also disappear, the context menu that appears when right clicking a window becomes a gigantic, oversized menu with 1 entry that takes up the entire monitor space.
(It may also freeze the window for a couple second before showing the broken menu)

The above journalctl errors seems to disappear after the second monitor is disabled, however all the issues persists until the affected application restarts. (So to recover, I need to disconnect my second monitor, then restart plasmashell, kwin and lattedock as these are the applications affected)

EXPECTED RESULT
None of the above should occur.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Debian GNU/Linux
KDE Plasma Version: 5.26.5
KDE Frameworks Version: 5.101.0
Qt Version: 6.1.0
Graphics Platform: X11

ADDITIONAL INFORMATION
- This seems to be a rather niche issue as there's only little information online (Apart from a reddit post I found below that has the exact same problem), but I can consistently reproduce it on my machine and I am forced to disable my second monitor at the moment.
https://www.reddit.com/r/archlinux/comments/y3v6ev/kde_missing_icons_in_x11_task_bar_is_just_blank

- Issue persists on Plasma 5.27 Beta, tested on a KDE Neon (Testing) Live session.
- No such issue seems to be found on Wayland. However Wayland has its own set of issues preventing me from using it as a daily driver.
Comment 1 Nate Graham 2023-01-27 19:48:22 UTC
> - Issue persists on Plasma 5.27 Beta, tested on a KDE Neon (Testing) Live session.
Darn.

How many screens do you have? Can you attach a screenshot or the Display Configuration page, or a photo of the physical arrangement that shows the problem appearing?

Does all of this still happen in a Wayland session?
Comment 2 Kenny Hui 2023-01-28 03:55:50 UTC
Created attachment 155718 [details]
Display configuration in System Settings
Comment 3 Kenny Hui 2023-01-28 03:59:05 UTC
(In reply to Nate Graham from comment #1)
> > - Issue persists on Plasma 5.27 Beta, tested on a KDE Neon (Testing) Live session.
> Darn.
> 
> How many screens do you have? Can you attach a screenshot or the Display
> Configuration page, or a photo of the physical arrangement that shows the
> problem appearing?
> 
> Does all of this still happen in a Wayland session?

I have just attached the Display Configuration screen, with 2 screen attached.
This issue does not happen on Wayland and seems to be X11 only.
Comment 4 David Edmundson 2023-02-01 16:50:46 UTC
kwin_x11[1568]: kf.config.core: "\"NaturalSize_inf\" - conversion of \"-2147483648,-2147483648\" to QSizeF failed" (When Task Switcher is opened)

This is coming from Plasma::Svg. 

Can you paste any surrounding log. 
Did this only happen on the Neon live image?
Comment 5 Kenny Hui 2023-02-01 18:34:39 UTC
(In reply to David Edmundson from comment #4)
> kwin_x11[1568]: kf.config.core: "\"NaturalSize_inf\" - conversion of
> \"-2147483648,-2147483648\" to QSizeF failed" (When Task Switcher is opened)
> 
> This is coming from Plasma::Svg. 
> 
> Can you paste any surrounding log. 
> Did this only happen on the Neon live image?

Feb 01 16:59:19 neon kwin_x11[1862]: kf.config.core: "\"NaturalSize_inf\" - conversion of \"-2147483648,-2147483648\" to QSizeF failed"
Feb 01 16:59:19 neon kwin_x11[1862]: kf.config.core: "\"NaturalSize_inf\" - conversion of \"-2147483648,-2147483648\" to QSizeF failed"
Feb 01 16:59:19 neon kwin_x11[1862]: kf.config.core: "\"NaturalSize_inf\" - conversion of \"-2147483648,-2147483648\" to QSizeF failed"
Feb 01 16:59:19 neon kwin_x11[1862]: kf.config.core: "\"NaturalSize_inf\" - conversion of \"-2147483648,-2147483648\" to QSizeF failed"
Feb 01 16:59:19 neon kwin_x11[1862]: qml: PlasmaExtras.ScrollArea is deprecated. Use PlasmaComponents3.ScrollView instead.
Feb 01 16:59:19 neon kwin_x11[1862]: kf.config.core: "\"NaturalSize_inf\" - conversion of \"-2147483648,-2147483648\" to QSizeF failed"
Feb 01 16:59:20 neon kwin_x11[1862]: kf.config.core: "\"NaturalSize_inf\" - conversion of \"-2147483648,-2147483648\" to QSizeF failed"
Feb 01 16:59:20 neon kwin_x11[1862]: kf.config.core: "\"NaturalSize_inf\" - conversion of \"-2147483648,-2147483648\" to QSizeF failed"
Feb 01 16:59:20 neon kwin_x11[1862]: kf.config.core: "\"NaturalSize_inf\" - conversion of \"-2147483648,-2147483648\" to QSizeF failed"
Feb 01 16:59:28 neon plasmashell[1882]: file:///usr/lib/x86_64-linux-gnu/qt5/qml/org/kde/plasma/extras/PlaceholderMessage.qml:238:5: QML Heading: Binding loop detected for property "verticalAlignment"
Feb 01 16:59:34 neon plasmashell[1882]: file:///usr/lib/x86_64-linux-gnu/qt5/qml/org/kde/plasma/extras/PlaceholderMessage.qml:238:5: QML Heading: Binding loop detected for property "verticalAlignment"
Feb 01 16:59:34 neon plasmashell[1882]: trying to show an empty dialog
Feb 01 16:59:34 neon plasmashell[1882]: trying to show an empty dialog
Feb 01 16:59:43 neon systemd[1716]: Started Dolphin - File Manager.
Feb 01 16:59:43 neon plasmashell[1882]: file:///usr/share/plasma/plasmoids/org.kde.plasma.taskmanager/contents/ui/Task.qml:281: Unable to assign [undefined] to QString
Feb 01 16:59:43 neon dolphin[2373]: org.kde.dolphin: Unknown class  ""  in session saved data!
Feb 01 16:59:43 neon dolphin[2373]: kf.kio.widgets: Cannot read information about filesystem under path "/home/neon/.cache/thumbnails/"
Feb 01 16:59:57 neon neon_flathub.rb[2355]: [1.9K blob data]
Feb 01 16:59:57 neon neon_flathub.rb[2412]: error: Can't load uri https://flathub.org/repo/flathub.flatpakrepo: Error resolving “flathub.org”: Temporary failure in name resolution
Feb 01 17:00:12 neon kwin_x11[1862]: kwin_core: XCB error: 152 (BadDamage), sequence: 22213, resource id: 33556037, major code: 143 (DAMAGE), minor code: 3 (Subtract)
Feb 01 17:00:21 neon plasmashell[1882]: QQmlEngine::setContextForObject(): Object already has a QQmlContext

This issue is not only limited to KDE Neon, however I often use Neon live session to test so it won't mess up my main desktop configuration.

So far I have been able to reproduce this on Neon (5.26.90), Debian testing (5.26.5) and Fedora 37 (5.26.2), and the same issue still persist after installation.

However Kubuntu 22.10 (Plasma 5.25.5) have none of these issues with multi-monitors, which may suggest this bug is introduced in the 5.26 series? (No hard evidence yet, will have to try another older distro for that)
Comment 6 Arjan Asadi 2023-02-05 21:31:56 UTC
I have the same issue. 

I'm using a dual monitor setup. (with nvidia, disabled kscreen 2)
If under TaskManager Settings > Behavior > Show only Tasks you select From current screen (https://imgur.com/a/i3o0pC6) I get the same problem, when I disable it task manager functions properly and shows up.

After sleep or restarting 
or plasmashell --replace & 
the bar becomes empty 

to temporarily fix this issue I put my second monitor on left side of my primary and then return it to right side position
(xrandr --output DISP1  --left-of DISP2 &&  xrandr --output DISP1  --right-of DISP2) and it fixes the issue
doing the same action through nvidia-settings has worked also

My best guess is some recent change to the classic Task Manager applet has caused this issue
Comment 7 Kenny Hui 2023-02-11 15:54:37 UTC
Hm, Fedora 36 Live session (Plasma 5.24.5) doesn't have this issue either.

A short recap:
- This is an X11 only bug, Wayland works fine.
- Nouveau and NVIDIA Proprietary driver does not make a difference
- This is not Distro dependent as far as I can tell.
- This is probably introduced in Plasma 5.26 as the version before (<=5.25.5) works fine.
- The 5.27 multi-monitor refactoring unfortunately does not seems to resolve this issue.
- It affects Window title (gone), Context menu (extremely oversized), Desktop icon/panel/panel widgets (Basically the entirety of plasmashell does not have any icon showing up) and Latte Dock (Again no icon, though I no longer use it)
- The application icon on the Window Title (Top left by default) & the <Minimize/Maximize/Close> button (Top right by default) still renders correctly with no issue.
- I am currently on a Desktop with 2 monitors connected.
- This bug happens as long as there's 2 monitor connected, no matter the order/which one is the primary.
- If I only activate either one monitor this bug won't occur. (But bug will persist until I restart the affected component/restart PC)

My Main monitor is "HDMI-1" (BenQ G2412HD). [Connected to my integrated GPU]
My 2nd monitor is "DVI-D-1-1" (LG Electronics-W2261-255252). [Connected to my NVIDIA card]
No other monitors are connected.

----------------------
kscreen-doctor -o:
----------------------

65 HDMI-1 enabled connected priority 1 HDMI Modes: 100:720x400@70 70:1920x1080@60*! 71:1920x1080@60 72:1920x1080@50 73:1920x1080@60 74:1920x1080@60 75:1920x1080@50 76:1920x1080@60 77:1680x1050@60 78:1600x900@60 79:1280x1024@75 80:1280x1024@60 81:1280x960@60 82:1152x864@75 83:1280x720@60 84:1280x720@50 85:1280x720@60 86:1024x768@75 87:1024x768@60 88:832x624@75 89:800x600@75 90:800x600@60 91:720x576@50 92:720x576@50 93:720x480@60 94:720x480@60 95:720x480@60 96:720x480@60 97:640x480@75 98:640x480@60 99:640x480@60 Geometry: 0,0 1920x1080 Scale: 1 Rotation: 1 Overscan: 0 Vrr: incapable RgbRange: unknown
Output: 66 HDMI-2 disabled disconnected priority 0 HDMI Modes: Geometry: 0,0 0x0 Scale: 1 Rotation: 1 Overscan: 0 Vrr: incapable RgbRange: unknown
Output: 67 DP-1 disabled disconnected priority 0 DisplayPort Modes: Geometry: 0,0 0x0 Scale: 1 Rotation: 1 Overscan: 0 Vrr: incapable RgbRange: unknown
Output: 68 HDMI-3 disabled disconnected priority 0 HDMI Modes: Geometry: 0,0 0x0 Scale: 1 Rotation: 1 Overscan: 0 Vrr: incapable RgbRange: unknown
Output: 151 DVI-I-1-1 disabled disconnected priority 0 DVI Modes: Geometry: 0,0 0x0 Scale: 1 Rotation: 1 Overscan: 0 Vrr: incapable RgbRange: unknown
Output: 152 HDMI-1-4 disabled disconnected priority 0 HDMI Modes: Geometry: 0,0 0x0 Scale: 1 Rotation: 1 Overscan: 0 Vrr: incapable RgbRange: unknown
Output: 153 DP-1-2 disabled disconnected priority 0 DisplayPort Modes: Geometry: 0,0 0x0 Scale: 1 Rotation: 1 Overscan: 0 Vrr: incapable RgbRange: unknown
Output: 154 DVI-D-1-1 enabled connected priority 2 DVI Modes: 100:720x400@70 156:1920x1080@60*! 157:1680x1050@60 158:1400x1050@60 159:1600x900@60 160:1280x1024@60 161:1400x900@60 162:1280x960@60 163:1440x810@60 164:1368x768@60 165:1280x800@60 166:1152x864@60 167:1280x720@60 168:1024x768@60 169:960x720@60 170:928x696@60 171:896x672@60 172:1024x576@60 173:960x600@60 174:832x624@60 175:960x540@60 176:800x600@60 177:800x600@56 178:840x525@60 179:864x486@60 180:700x525@60 181:800x450@60 182:640x512@60 183:700x450@60 184:640x480@60 185:720x405@60 186:684x384@60 187:576x432@60 188:640x360@60 189:512x384@60 190:512x288@60 191:416x312@60 192:480x270@60 193:400x300@60 194:432x243@60 195:320x240@60 196:360x202@60 197:320x180@60 71:1920x1080@60 77:1680x1050@60 79:1280x1024@75 80:1280x1024@60 81:1280x960@60 82:1152x864@75 86:1024x768@75 87:1024x768@60 88:832x624@75 89:800x600@75 90:800x600@60 97:640x480@75 99:640x480@60 Geometry: 1920,0 1920x1080 Scale: 1 Rotation: 1 Overscan: 0 Vrr: incapable RgbRange: unknown

----------------------
kscreen-console:
----------------------

START: Requesting Config
Received config. Took 19 milliseconds
Screen:
        maxSize: QSize(16384, 16384)
        minSize: QSize(320, 200)
        currentSize: QSize(3840, 1080)

-----------------------------------------------------

Id:  65
Name:  "HDMI-1"
Type:  "HDMI"
Connected:  true
Enabled:  true
Priority:  1
Rotation:  KScreen::Output::None
Pos:  QPoint(0,0)
MMSize:  QSize(521, 293)
FollowPreferredMode:  false
Size:  QSize(1920, 1080)
Scale:  1
Clones:  None
Mode:  "70"
Preferred Mode:  "70"
Preferred modes:  ("70")
Modes: 
         "100"    ""   QSize(720, 400)   70.0817
         "70"    ""   QSize(1920, 1080)   60
         "71"    ""   QSize(1920, 1080)   60
         "72"    ""   QSize(1920, 1080)   50
         "73"    ""   QSize(1920, 1080)   59.9402
         "74"    ""   QSize(1920, 1080)   60
         "75"    ""   QSize(1920, 1080)   50
         "76"    ""   QSize(1920, 1080)   59.9402
         "77"    ""   QSize(1680, 1050)   59.8833
         "78"    ""   QSize(1600, 900)   60
         "79"    ""   QSize(1280, 1024)   75.0247
         "80"    ""   QSize(1280, 1024)   60.0197
         "81"    ""   QSize(1280, 960)   60
         "82"    ""   QSize(1152, 864)   75
         "83"    ""   QSize(1280, 720)   60
         "84"    ""   QSize(1280, 720)   50
         "85"    ""   QSize(1280, 720)   59.9402
         "86"    ""   QSize(1024, 768)   75.0286
         "87"    ""   QSize(1024, 768)   60.0038
         "88"    ""   QSize(832, 624)   74.5513
         "89"    ""   QSize(800, 600)   75
         "90"    ""   QSize(800, 600)   60.3165
         "91"    ""   QSize(720, 576)   50
         "92"    ""   QSize(720, 576)   50
         "93"    ""   QSize(720, 480)   60
         "94"    ""   QSize(720, 480)   59.9401
         "95"    ""   QSize(720, 480)   60.0022
         "96"    ""   QSize(720, 480)   59.9401
         "97"    ""   QSize(640, 480)   75
         "98"    ""   QSize(640, 480)   60
         "99"    ""   QSize(640, 480)   59.9405
EDID Info: 
        Device ID:  "xrandr-BenQ G2412HD-M3903852CL0"
        Name:  "BenQ G2412HD"
        Vendor:  ""
        Serial:  "M3903852CL0"
        EISA ID:  ""
        Hash:  "0de4986bb5ef93516362f7d66f986256"
        Width:  52
        Height:  29
        Gamma:  2.2
        Red:  QQuaternion(scalar:1, vector:(0.647461, 0.332031, 0))
        Green:  QQuaternion(scalar:1, vector:(0.28418, 0.607422, 0))
        Blue:  QQuaternion(scalar:1, vector:(0.151367, 0.0712891, 0))
        White:  QQuaternion(scalar:1, vector:(0.3125, 0.329102, 0))

-----------------------------------------------------

Id:  66
Name:  "HDMI-2"
Type:  "HDMI"
Connected:  false

-----------------------------------------------------

Id:  67
Name:  "DP-1"
Type:  "DisplayPort"
Connected:  false

-----------------------------------------------------

Id:  68
Name:  "HDMI-3"
Type:  "HDMI"
Connected:  false

-----------------------------------------------------

Id:  151
Name:  "DVI-I-1-1"
Type:  "DVI"
Connected:  false

-----------------------------------------------------

Id:  152
Name:  "HDMI-1-4"
Type:  "HDMI"
Connected:  false

-----------------------------------------------------

Id:  153
Name:  "DP-1-2"
Type:  "DisplayPort"
Connected:  false

-----------------------------------------------------

Id:  154
Name:  "DVI-D-1-1"
Type:  "DVI"
Connected:  true
Enabled:  true
Priority:  2
Rotation:  KScreen::Output::None
Pos:  QPoint(1920,0)
MMSize:  QSize(477, 268)
FollowPreferredMode:  false
Size:  QSize(1920, 1080)
Scale:  1
Clones:  None
Mode:  "156"
Preferred Mode:  "156"
Preferred modes:  ("156")
Modes: 
         "100"    ""   QSize(720, 400)   70.0817
         "156"    ""   QSize(1920, 1080)   59.9339
         "157"    ""   QSize(1680, 1050)   59.9336
         "158"    ""   QSize(1400, 1050)   59.9338
         "159"    ""   QSize(1600, 900)   59.9334
         "160"    ""   QSize(1280, 1024)   59.9336
         "161"    ""   QSize(1400, 900)   59.9338
         "162"    ""   QSize(1280, 960)   59.9333
         "163"    ""   QSize(1440, 810)   59.9336
         "164"    ""   QSize(1368, 768)   59.9336
         "165"    ""   QSize(1280, 800)   59.9332
         "166"    ""   QSize(1152, 864)   59.9333
         "167"    ""   QSize(1280, 720)   59.9331
         "168"    ""   QSize(1024, 768)   59.9337
         "169"    ""   QSize(960, 720)   59.9338
         "170"    ""   QSize(928, 696)   59.9335
         "171"    ""   QSize(896, 672)   59.9336
         "172"    ""   QSize(1024, 576)   59.9335
         "173"    ""   QSize(960, 600)   59.9333
         "174"    ""   QSize(832, 624)   59.9336
         "175"    ""   QSize(960, 540)   59.9338
         "176"    ""   QSize(800, 600)   59.9328
         "177"    ""   QSize(800, 600)   56.25
         "178"    ""   QSize(840, 525)   59.9336
         "179"    ""   QSize(864, 486)   59.9336
         "180"    ""   QSize(700, 525)   59.9333
         "181"    ""   QSize(800, 450)   59.9328
         "182"    ""   QSize(640, 512)   59.933
         "183"    ""   QSize(700, 450)   59.9338
         "184"    ""   QSize(640, 480)   59.9333
         "185"    ""   QSize(720, 405)   59.9317
         "186"    ""   QSize(684, 384)   59.9327
         "187"    ""   QSize(576, 432)   59.9333
         "188"    ""   QSize(640, 360)   59.9332
         "189"    ""   QSize(512, 384)   59.9337
         "190"    ""   QSize(512, 288)   59.932
         "191"    ""   QSize(416, 312)   59.9323
         "192"    ""   QSize(480, 270)   59.9338
         "193"    ""   QSize(400, 300)   59.9334
         "194"    ""   QSize(432, 243)   59.9336
         "195"    ""   QSize(320, 240)   59.9332
         "196"    ""   QSize(360, 202)   59.9337
         "197"    ""   QSize(320, 180)   59.9332
         "71"    ""   QSize(1920, 1080)   60
         "77"    ""   QSize(1680, 1050)   59.8833
         "79"    ""   QSize(1280, 1024)   75.0247
         "80"    ""   QSize(1280, 1024)   60.0197
         "81"    ""   QSize(1280, 960)   60
         "82"    ""   QSize(1152, 864)   75
         "86"    ""   QSize(1024, 768)   75.0286
         "87"    ""   QSize(1024, 768)   60.0038
         "88"    ""   QSize(832, 624)   74.5513
         "89"    ""   QSize(800, 600)   75
         "90"    ""   QSize(800, 600)   60.3165
         "97"    ""   QSize(640, 480)   75
         "99"    ""   QSize(640, 480)   59.9405
EDID Info: 
        Device ID:  "xrandr-LG Electronics-W2261-255252"
        Name:  "W2261"
        Vendor:  "LG Electronics"
        Serial:  "255252"
        EISA ID:  ""
        Hash:  "f153eb9074d08a54acbb1b335aa2a4c1"
        Width:  48
        Height:  27
        Gamma:  2.2
        Red:  QQuaternion(scalar:1, vector:(0.648438, 0.335938, 0))
        Green:  QQuaternion(scalar:1, vector:(0.291992, 0.602539, 0))
        Blue:  QQuaternion(scalar:1, vector:(0.142578, 0.0703125, 0))
        White:  QQuaternion(scalar:1, vector:(0.313477, 0.329102, 0))
Comment 8 Arjan Asadi 2023-02-12 00:49:02 UTC
(In reply to kenny.mh.hui from comment #7)
> Hm, Fedora 36 Live session (Plasma 5.24.5) doesn't have this issue either.
> 
> A short recap:
> - This is an X11 only bug, Wayland works fine.
> - Nouveau and NVIDIA Proprietary driver does not make a difference
> - This is not Distro dependent as far as I can tell.
> - This is probably introduced in Plasma 5.26 as the version before
> (<=5.25.5) works fine.
> - The 5.27 multi-monitor refactoring unfortunately does not seems to resolve
> this issue.
> - It affects Window title (gone), Context menu (extremely oversized),
> Desktop icon/panel/panel widgets (Basically the entirety of plasmashell does
> not have any icon showing up) and Latte Dock (Again no icon, though I no
> longer use it)
> - The application icon on the Window Title (Top left by default) & the
> <Minimize/Maximize/Close> button (Top right by default) still renders
> correctly with no issue.
> - I am currently on a Desktop with 2 monitors connected.
> - This bug happens as long as there's 2 monitor connected, no matter the
> order/which one is the primary.
> - If I only activate either one monitor this bug won't occur. (But bug will
> persist until I restart the affected component/restart PC)
> 
> My Main monitor is "HDMI-1" (BenQ G2412HD). [Connected to my integrated GPU]
> My 2nd monitor is "DVI-D-1-1" (LG Electronics-W2261-255252). [Connected to
> my NVIDIA card]
> No other monitors are connected.
> 
> ----------------------
> kscreen-doctor -o:
> ----------------------
> 
> 65 HDMI-1 enabled connected priority 1 HDMI Modes: 100:720x400@70
> 70:1920x1080@60*! 71:1920x1080@60 72:1920x1080@50 73:1920x1080@60
> 74:1920x1080@60 75:1920x1080@50 76:1920x1080@60 77:1680x1050@60
> 78:1600x900@60 79:1280x1024@75 80:1280x1024@60 81:1280x960@60 82:1152x864@75
> 83:1280x720@60 84:1280x720@50 85:1280x720@60 86:1024x768@75 87:1024x768@60
> 88:832x624@75 89:800x600@75 90:800x600@60 91:720x576@50 92:720x576@50
> 93:720x480@60 94:720x480@60 95:720x480@60 96:720x480@60 97:640x480@75
> 98:640x480@60 99:640x480@60 Geometry: 0,0 1920x1080 Scale: 1 Rotation: 1
> Overscan: 0 Vrr: incapable RgbRange: unknown
> Output: 66 HDMI-2 disabled disconnected priority 0 HDMI Modes: Geometry: 0,0
> 0x0 Scale: 1 Rotation: 1 Overscan: 0 Vrr: incapable RgbRange: unknown
> Output: 67 DP-1 disabled disconnected priority 0 DisplayPort Modes:
> Geometry: 0,0 0x0 Scale: 1 Rotation: 1 Overscan: 0 Vrr: incapable RgbRange:
> unknown
> Output: 68 HDMI-3 disabled disconnected priority 0 HDMI Modes: Geometry: 0,0
> 0x0 Scale: 1 Rotation: 1 Overscan: 0 Vrr: incapable RgbRange: unknown
> Output: 151 DVI-I-1-1 disabled disconnected priority 0 DVI Modes: Geometry:
> 0,0 0x0 Scale: 1 Rotation: 1 Overscan: 0 Vrr: incapable RgbRange: unknown
> Output: 152 HDMI-1-4 disabled disconnected priority 0 HDMI Modes: Geometry:
> 0,0 0x0 Scale: 1 Rotation: 1 Overscan: 0 Vrr: incapable RgbRange: unknown
> Output: 153 DP-1-2 disabled disconnected priority 0 DisplayPort Modes:
> Geometry: 0,0 0x0 Scale: 1 Rotation: 1 Overscan: 0 Vrr: incapable RgbRange:
> unknown
> Output: 154 DVI-D-1-1 enabled connected priority 2 DVI Modes: 100:720x400@70
> 156:1920x1080@60*! 157:1680x1050@60 158:1400x1050@60 159:1600x900@60
> 160:1280x1024@60 161:1400x900@60 162:1280x960@60 163:1440x810@60
> 164:1368x768@60 165:1280x800@60 166:1152x864@60 167:1280x720@60
> 168:1024x768@60 169:960x720@60 170:928x696@60 171:896x672@60 172:1024x576@60
> 173:960x600@60 174:832x624@60 175:960x540@60 176:800x600@60 177:800x600@56
> 178:840x525@60 179:864x486@60 180:700x525@60 181:800x450@60 182:640x512@60
> 183:700x450@60 184:640x480@60 185:720x405@60 186:684x384@60 187:576x432@60
> 188:640x360@60 189:512x384@60 190:512x288@60 191:416x312@60 192:480x270@60
> 193:400x300@60 194:432x243@60 195:320x240@60 196:360x202@60 197:320x180@60
> 71:1920x1080@60 77:1680x1050@60 79:1280x1024@75 80:1280x1024@60
> 81:1280x960@60 82:1152x864@75 86:1024x768@75 87:1024x768@60 88:832x624@75
> 89:800x600@75 90:800x600@60 97:640x480@75 99:640x480@60 Geometry: 1920,0
> 1920x1080 Scale: 1 Rotation: 1 Overscan: 0 Vrr: incapable RgbRange: unknown
> 
> ----------------------
> kscreen-console:
> ----------------------
> 
> START: Requesting Config
> Received config. Took 19 milliseconds
> Screen:
>         maxSize: QSize(16384, 16384)
>         minSize: QSize(320, 200)
>         currentSize: QSize(3840, 1080)
> 
> -----------------------------------------------------
> 
> Id:  65
> Name:  "HDMI-1"
> Type:  "HDMI"
> Connected:  true
> Enabled:  true
> Priority:  1
> Rotation:  KScreen::Output::None
> Pos:  QPoint(0,0)
> MMSize:  QSize(521, 293)
> FollowPreferredMode:  false
> Size:  QSize(1920, 1080)
> Scale:  1
> Clones:  None
> Mode:  "70"
> Preferred Mode:  "70"
> Preferred modes:  ("70")
> Modes: 
>          "100"    ""   QSize(720, 400)   70.0817
>          "70"    ""   QSize(1920, 1080)   60
>          "71"    ""   QSize(1920, 1080)   60
>          "72"    ""   QSize(1920, 1080)   50
>          "73"    ""   QSize(1920, 1080)   59.9402
>          "74"    ""   QSize(1920, 1080)   60
>          "75"    ""   QSize(1920, 1080)   50
>          "76"    ""   QSize(1920, 1080)   59.9402
>          "77"    ""   QSize(1680, 1050)   59.8833
>          "78"    ""   QSize(1600, 900)   60
>          "79"    ""   QSize(1280, 1024)   75.0247
>          "80"    ""   QSize(1280, 1024)   60.0197
>          "81"    ""   QSize(1280, 960)   60
>          "82"    ""   QSize(1152, 864)   75
>          "83"    ""   QSize(1280, 720)   60
>          "84"    ""   QSize(1280, 720)   50
>          "85"    ""   QSize(1280, 720)   59.9402
>          "86"    ""   QSize(1024, 768)   75.0286
>          "87"    ""   QSize(1024, 768)   60.0038
>          "88"    ""   QSize(832, 624)   74.5513
>          "89"    ""   QSize(800, 600)   75
>          "90"    ""   QSize(800, 600)   60.3165
>          "91"    ""   QSize(720, 576)   50
>          "92"    ""   QSize(720, 576)   50
>          "93"    ""   QSize(720, 480)   60
>          "94"    ""   QSize(720, 480)   59.9401
>          "95"    ""   QSize(720, 480)   60.0022
>          "96"    ""   QSize(720, 480)   59.9401
>          "97"    ""   QSize(640, 480)   75
>          "98"    ""   QSize(640, 480)   60
>          "99"    ""   QSize(640, 480)   59.9405
> EDID Info: 
>         Device ID:  "xrandr-BenQ G2412HD-M3903852CL0"
>         Name:  "BenQ G2412HD"
>         Vendor:  ""
>         Serial:  "M3903852CL0"
>         EISA ID:  ""
>         Hash:  "0de4986bb5ef93516362f7d66f986256"
>         Width:  52
>         Height:  29
>         Gamma:  2.2
>         Red:  QQuaternion(scalar:1, vector:(0.647461, 0.332031, 0))
>         Green:  QQuaternion(scalar:1, vector:(0.28418, 0.607422, 0))
>         Blue:  QQuaternion(scalar:1, vector:(0.151367, 0.0712891, 0))
>         White:  QQuaternion(scalar:1, vector:(0.3125, 0.329102, 0))
> 
> -----------------------------------------------------
> 
> Id:  66
> Name:  "HDMI-2"
> Type:  "HDMI"
> Connected:  false
> 
> -----------------------------------------------------
> 
> Id:  67
> Name:  "DP-1"
> Type:  "DisplayPort"
> Connected:  false
> 
> -----------------------------------------------------
> 
> Id:  68
> Name:  "HDMI-3"
> Type:  "HDMI"
> Connected:  false
> 
> -----------------------------------------------------
> 
> Id:  151
> Name:  "DVI-I-1-1"
> Type:  "DVI"
> Connected:  false
> 
> -----------------------------------------------------
> 
> Id:  152
> Name:  "HDMI-1-4"
> Type:  "HDMI"
> Connected:  false
> 
> -----------------------------------------------------
> 
> Id:  153
> Name:  "DP-1-2"
> Type:  "DisplayPort"
> Connected:  false
> 
> -----------------------------------------------------
> 
> Id:  154
> Name:  "DVI-D-1-1"
> Type:  "DVI"
> Connected:  true
> Enabled:  true
> Priority:  2
> Rotation:  KScreen::Output::None
> Pos:  QPoint(1920,0)
> MMSize:  QSize(477, 268)
> FollowPreferredMode:  false
> Size:  QSize(1920, 1080)
> Scale:  1
> Clones:  None
> Mode:  "156"
> Preferred Mode:  "156"
> Preferred modes:  ("156")
> Modes: 
>          "100"    ""   QSize(720, 400)   70.0817
>          "156"    ""   QSize(1920, 1080)   59.9339
>          "157"    ""   QSize(1680, 1050)   59.9336
>          "158"    ""   QSize(1400, 1050)   59.9338
>          "159"    ""   QSize(1600, 900)   59.9334
>          "160"    ""   QSize(1280, 1024)   59.9336
>          "161"    ""   QSize(1400, 900)   59.9338
>          "162"    ""   QSize(1280, 960)   59.9333
>          "163"    ""   QSize(1440, 810)   59.9336
>          "164"    ""   QSize(1368, 768)   59.9336
>          "165"    ""   QSize(1280, 800)   59.9332
>          "166"    ""   QSize(1152, 864)   59.9333
>          "167"    ""   QSize(1280, 720)   59.9331
>          "168"    ""   QSize(1024, 768)   59.9337
>          "169"    ""   QSize(960, 720)   59.9338
>          "170"    ""   QSize(928, 696)   59.9335
>          "171"    ""   QSize(896, 672)   59.9336
>          "172"    ""   QSize(1024, 576)   59.9335
>          "173"    ""   QSize(960, 600)   59.9333
>          "174"    ""   QSize(832, 624)   59.9336
>          "175"    ""   QSize(960, 540)   59.9338
>          "176"    ""   QSize(800, 600)   59.9328
>          "177"    ""   QSize(800, 600)   56.25
>          "178"    ""   QSize(840, 525)   59.9336
>          "179"    ""   QSize(864, 486)   59.9336
>          "180"    ""   QSize(700, 525)   59.9333
>          "181"    ""   QSize(800, 450)   59.9328
>          "182"    ""   QSize(640, 512)   59.933
>          "183"    ""   QSize(700, 450)   59.9338
>          "184"    ""   QSize(640, 480)   59.9333
>          "185"    ""   QSize(720, 405)   59.9317
>          "186"    ""   QSize(684, 384)   59.9327
>          "187"    ""   QSize(576, 432)   59.9333
>          "188"    ""   QSize(640, 360)   59.9332
>          "189"    ""   QSize(512, 384)   59.9337
>          "190"    ""   QSize(512, 288)   59.932
>          "191"    ""   QSize(416, 312)   59.9323
>          "192"    ""   QSize(480, 270)   59.9338
>          "193"    ""   QSize(400, 300)   59.9334
>          "194"    ""   QSize(432, 243)   59.9336
>          "195"    ""   QSize(320, 240)   59.9332
>          "196"    ""   QSize(360, 202)   59.9337
>          "197"    ""   QSize(320, 180)   59.9332
>          "71"    ""   QSize(1920, 1080)   60
>          "77"    ""   QSize(1680, 1050)   59.8833
>          "79"    ""   QSize(1280, 1024)   75.0247
>          "80"    ""   QSize(1280, 1024)   60.0197
>          "81"    ""   QSize(1280, 960)   60
>          "82"    ""   QSize(1152, 864)   75
>          "86"    ""   QSize(1024, 768)   75.0286
>          "87"    ""   QSize(1024, 768)   60.0038
>          "88"    ""   QSize(832, 624)   74.5513
>          "89"    ""   QSize(800, 600)   75
>          "90"    ""   QSize(800, 600)   60.3165
>          "97"    ""   QSize(640, 480)   75
>          "99"    ""   QSize(640, 480)   59.9405
> EDID Info: 
>         Device ID:  "xrandr-LG Electronics-W2261-255252"
>         Name:  "W2261"
>         Vendor:  "LG Electronics"
>         Serial:  "255252"
>         EISA ID:  ""
>         Hash:  "f153eb9074d08a54acbb1b335aa2a4c1"
>         Width:  48
>         Height:  27
>         Gamma:  2.2
>         Red:  QQuaternion(scalar:1, vector:(0.648438, 0.335938, 0))
>         Green:  QQuaternion(scalar:1, vector:(0.291992, 0.602539, 0))
>         Blue:  QQuaternion(scalar:1, vector:(0.142578, 0.0703125, 0))
>         White:  QQuaternion(scalar:1, vector:(0.313477, 0.329102, 0))

did you select TaskManager Settings > Behavior > Show only Tasks you select From current screen as I mentioned? 
If I don't select this my task manager works fine if I select it, it disappears
Comment 9 Kenny Hui 2023-02-12 04:45:16 UTC
(In reply to Arjan Asadi from comment #8)
> did you select TaskManager Settings > Behavior > Show only Tasks you select
> From current screen as I mentioned? 
> If I don't select this my task manager works fine if I select it, it
> disappears

Nope, it happens regardless. Swapping the monitor doesn't do anything as well
We might be hitting a different bug, does anything above occurs to you apart from the task manager icon not showing?
Comment 10 Arjan Asadi 2023-02-13 03:01:36 UTC
(In reply to kenny.mh.hui from comment #9)
> (In reply to Arjan Asadi from comment #8)
> > did you select TaskManager Settings > Behavior > Show only Tasks you select
> > From current screen as I mentioned? 
> > If I don't select this my task manager works fine if I select it, it
> > disappears
> 
> Nope, it happens regardless. Swapping the monitor doesn't do anything as well
> We might be hitting a different bug, does anything above occurs to you apart
> from the task manager icon not showing?

the only thing I encounter is the task manager disappearing. I click on the "From current screen" and it disappears, click on it again and apply and it appears again. very strange
Comment 11 Arjan Asadi 2023-02-14 12:33:01 UTC
(In reply to Arjan Asadi from comment #10)
> (In reply to kenny.mh.hui from comment #9)
> > (In reply to Arjan Asadi from comment #8)
> > > did you select TaskManager Settings > Behavior > Show only Tasks you select
> > > From current screen as I mentioned? 
> > > If I don't select this my task manager works fine if I select it, it
> > > disappears
> > 
> > Nope, it happens regardless. Swapping the monitor doesn't do anything as well
> > We might be hitting a different bug, does anything above occurs to you apart
> > from the task manager icon not showing?
> 
> the only thing I encounter is the task manager disappearing. I click on the
> "From current screen" and it disappears, click on it again and apply and it
> appears again. very strange

5.26.90 kde doesn't have this problem, 5.26.5-1 had it. 
so I enabled unstable-kde repos and my kde got more stable.
Comment 12 Nate Graham 2023-02-14 17:42:02 UTC
Makes sense, because we did a ton of multiscreen stability fork for Plasma 5.27!
Comment 13 Arjan Asadi 2023-02-15 01:54:33 UTC
(In reply to Nate Graham from comment #12)
> Makes sense, because we did a ton of multiscreen stability fork for Plasma
> 5.27!

now I upgraded to 5.27 and the bug is back!
5.26.90 KDE doesn't have this problem, 5.26.5-1 had it.
Comment 14 Arjan Asadi 2023-02-15 04:25:23 UTC
(In reply to Arjan Asadi from comment #13)
> (In reply to Nate Graham from comment #12)
> > Makes sense, because we did a ton of multiscreen stability fork for Plasma
> > 5.27!
> 
> now I upgraded to 5.27 and the bug is back!
> 5.26.90 KDE doesn't have this problem, 5.26.5-1 had it.

after restarting it seems to be fixed
Comment 15 Kenny Hui 2023-02-15 08:20:25 UTC
The task manager issue (Probably a separate bug) might be fixed, but the issue reported still persists as of the official 5.27.0 release.
On the other hand Plasma Wayland support have gotten more mature esp in 5.27, and I'll stay on Wayland for the time-being.
But the issue reported is still is an (atm unresolved) bug on X11, and those who relies on X11 may also encounter this issue.

I am happy to provide any further information when requested for this bug to be resolved.
Comment 16 Kenny Hui 2023-02-15 08:39:33 UTC
Update: I am now able to workaround the issue:
1. Disable the secondary monitor
2. Log out, log back in
3. Re-enable the secondary monitor

https://forum.endeavouros.com/t/kde-plasma-has-weird-behavior-after-update-and-reboot/33150/29?page=2
Comment 17 Arjan Asadi 2023-02-15 09:48:32 UTC
(In reply to kenny.mh.hui from comment #15)
> The task manager issue (Probably a separate bug) might be fixed, but the
> issue reported still persists as of the official 5.27.0 release.
> On the other hand Plasma Wayland support have gotten more mature esp in
> 5.27, and I'll stay on Wayland for the time-being.
> But the issue reported is still is an (atm unresolved) bug on X11, and those
> who relies on X11 may also encounter this issue.
> 
> I am happy to provide any further information when requested for this bug to
> be resolved.

there was a co-occuring bug that is also fixed on 5.27 for me,  Global Menu was also empty which now isn't anymore
Comment 18 Nate Graham 2023-02-17 17:09:59 UTC
Let's keep the focus on the issue that Kenny is experiencing. Kenny, can you clarify what's still reproducing on X11 with Plasma 5.27.0?
Comment 19 Kenny Hui 2023-02-17 18:56:52 UTC
(In reply to Nate Graham from comment #18)
> Let's keep the focus on the issue that Kenny is experiencing. Kenny, can you
> clarify what's still reproducing on X11 with Plasma 5.27.0?

I am currently experiencing missing icon on the plasmashell (The panel, desktop icon, widgets), a wrongly-sized right-click menu and missing title text on each window's titlebar.

This only occurs when a plasma session is started with 2 monitors enabled. (So if you disable or maybe unplug one of your monitor when logging in, then reactivate that monitor within that session it will work fine).

journalctl doesn't indicate anything interesting either, all I know is this bug only happens on Plasma 5.26 and above.

Here's another user experiencing the same issue (Already posted above):
https://forum.endeavouros.com/t/kde-plasma-has-weird-behavior-after-update-and-reboot/33150

The only difference between the user from the link above and my case is that the right click menu takes up my entire screen height instead of only stretching the width, but I believe we are hitting the same bug.

The answer linked from the above post says that "If it works, it is a bug that will not take long to fix", I am not sure whether this is a duplicate as I couldn't find any, but at least this bug seems to have been known for quite sometimes now.

Not sure how much correlations this has with kwin though, I only reported it here since it affected the titlebar as well.
Comment 20 Kenny Hui 2023-03-04 09:56:28 UTC
Ah https://bugs.kde.org/show_bug.cgi?id=462725
Duplicate, ought to be fixed in 5.27.2

*** This bug has been marked as a duplicate of bug 462725 ***