Display off edges of monitor

[mappop]

Hi, I am having an issue with the display on my external monitor. The area Plasma is using is larger than the screen so much of the information isn't shown on any maximized window. For example, when I maximize Chrome I can barely see the bottom edge of the tab bar, I cannot see the Minimize/maximize/close buttons, and the cursor can disappear off the edge of the screen on all 4 sides. As this monitor is a secondary display this leaves an invisible gap between the bottom of the external display and the top of the primary display. It occurs on the external monitor regardless even if I switch it to the primary display, or if I disable the other monitor. It only occurs on the external monitor, the internal (laptop) primary monitor is fine. The display is correct on the login screens on both monitors, so it seems like it is a plasma issue, not a system issue. The problem started a week ago or so after applying some updates on my jammy installation. In an attempt to resolve the issue I upgraded to kinetic and it is still a problem. My monitor is rotated, but it occurs in all orientations. I made no changes to the system configuration and cannot find any settings to change that would effect the display in plasma. The monitor is a Dell S2409W using HDMI and the graphics card is a Mesa Intel HD Graphics 3000 on a Dell i3520 laptop.

Please advise where I might turn to resolve this issue.

*Update: It occurs only when using X11. The display is correct when using Wayland.
*Update 2: The issue does not appear on the Ubuntu Desktop Gnome Xorg either. Appears to be a Kubuntu/Plasma X11 issue.
*Update 3: FWIW the Xrandr output is the same when using Gmone/xorg as it is using Plasma/X11. Since Gnome'xorg displays correctly it appears to be an error with the way Plasma is using the configuration, not with the configuration.
*Update 4: Also note that the display on the external monitor under Plasma/X11 is "shaky" as though it is using an incorrect refresh rate.

[claydoh]

What resolution is it using in x11 vs wayland? I wonder if there is a slight difference there, perhaps? Have you looked at what the monitor settings are showing?

If it were me, I'd stick with Wayland myself, even more so particularly if the laptop has touch, is 'convertible', and/or you use gestures.
In X11 you probably would have to futz about with custom xrandr setups and create custom scripts or something along those lines.

[mappop]

What resolution is it using in x11 vs wayland? I wonder if there is a slight difference there, perhaps? Have you looked at what the monitor settings are showing?

If it were me, I'd stick with Wayland myself, even more so particularly if the laptop has touch, is 'convertible', and/or you use gestures.
In X11 you probably would have to futz about with custom xrandr setups and create custom scripts or something along those lines.

Both are set to the monitor resolution, which is 1920x1080

[mappop]

What resolution is it using in x11 vs wayland? I wonder if there is a slight difference there, perhaps? Have you looked at what the monitor settings are showing?

If it were me, I'd stick with Wayland myself, even more so particularly if the laptop has touch, is 'convertible', and/or you use gestures.
In X11 you probably would have to futz about with custom xrandr setups and create custom scripts or something along those lines.

Regarding your suggestion to "stick with Wayland", please note that Wayland does not work with all applications. In particular I need Barrier/Synergy support, but those are not the only unsupported apps.

Also, this appears to be a bug, not just an inconvenience, as it worked up until a week or two ago, and should be fixed, so just ignoring it and using Wayland isn't a great way to go regardless.

[claydoh]

I was offering potential suggestions, using the information provided. You said it was working there.


Have you tried any of the basics, such as different cables, to eliminate potentially easier-to-troubleshoot non-software causes, particularly on what appears to be an old model of monitor?
Yes, it sounds silly, but it is an easy thing to eliminate nonetheless.
The logon screen is very likely not using the same resolution setting as the desktop session.

Do things work correctly in a live USB session?

You *might* try deleting or moving/renaming your kscreen configurations (~/.local/share/kscreen/) and log out/reboot), though I don't *think* this will help in this situation.

You can see how to get monitor information as well as some basic xrandr usage information here: https://linuxconfig.org/how-to-confi...randr-in-linux
Seeing some extra details on your external monitor's current settings and capabilities might reveal useful info, and hopefully point to a solution.

If the OS is reporting the correct resolution output, then it seems that x11 somehow on your particular hardware or monitor needs an overscan adjustment or something along those lines.
Sure, it well could be a bug, but on old hardware, and with monitors of such vintage being notorious for not reporting EDID information to proper specs consistently, this isn't always easy to manage. An update could have revelaed such a bad EDID, perhaps.

Basically, there could be many causes, as well as many potential fixes, so it may take some digging. Hopefully not much.

just ignoring it and using Wayland

Believe it or not, Wayland is not ignoring it, it is what is fixing things, since it is what xorg devs have all moved on to.
Maybe not today, for all, mind you.

It doesn't help that Plasma and multi-monitor support seem to be notoriously buggy/bad right now, no matter the display server.

[oshunluvr]

I'm just going to throw this in here:

I have had ALL KINDS of issues with kscreen2 for YEARS. Including this week. TL/DR: Remove kscreen2 and manually configure your monitors by using various xorg configuration files in /etc/X11/xorg.conf.d/ as needed, or write a script using xrandr that runs at log in. Doing this might fix this issue for you.

I built a new PC with a new KDEneon install and the monitor situation went batty as at always seems to. This time, it would randomly move all my windows to the right monitor, sometimes blacken the left monitor desktop, sometimes the left monitor would go off and stay off, etc. ad nauseam. I was just about convinced that the left monitor was the problem when I decided to remove my old nemesis kcreen2 and see what happened. 4 days have passed and no more batty behavior. Previously, I had removed kscreen2 from my laptop because my external monitor only supported 75hz and full resolution and kcreens2 always forced it to 60hz causing a black screen. Once I figured out kscreen2 was the issue, I removed it and wrote a script to set the monitors correctly using xrandr.

As far as I can tell, no one needs kcreeen2 unless you have a situation that your monitor setup changes from time to time. Even then, it's not always a viable solution.

[claydoh]

TL/DR: Remove kscreen2 and manually configure your monitors by using various xorg configuration files in /etc/X11/xorg.conf.d/ as needed, or write a script using xrandr that runs at log in. Doing this might fix this issue for you.

So how does the newbie or average layman do this?
Is there a particular set of good instructions on this you can recommend?


This mess is supposedly being addressed in Plasma 5.27. So Kubuntu users wouldn't see anything before 23.04 at best.

[Schwarzer Kater]

[…]
This mess is supposedly being addressed in Plasma 5.27. So Kubuntu users wouldn't see anything before 23.04 at best.

So everybody keep their fingers crossed for Kubuntu backports!

[claydoh]

So everybody keep their fingers crossed for Kubuntu backports!

By the time it's out for 22.10, 23.04 will be just around the corner anyway (that is where the packages would come from). But there should be some overlap, and Plasma betas, I am sure
5.27 should be in early February, so it should hit 23.10 pre-release shortly afterward, and (hopefully) backports shortly after that. So I guesstimate Kinetic users might get this a month before Lunar, or thereabouts.

[oshunluvr]

So how does the newbie or average layman do this?
Is there a particular set of good instructions on this you can recommend?

This mess is supposedly being addressed in Plasma 5.27. So Kubuntu users wouldn't see anything before 23.04 at best.

Well, honestly - at least for me - I didn't have to do anything. It "just works" without any added configuration.

The default files are in /usr/share/X11/xorg.conf.d. The way you're supposed to do it is create the /etc/xorg.conf.d folder and then add files in it to handle any fine-tuning adjustments. The files basically contain the sections of the old style xorg.conf file separated into separate files. You can also just use an xorg.conf file like we used to.

As usual, Arch has a very complete wiki.

[mappop]

I was offering potential suggestions, using the information provided. You said it was working there.


Have you tried any of the basics, such as different cables, to eliminate potentially easier-to-troubleshoot non-software causes, particularly on what appears to be an old model of monitor?
Yes, it sounds silly, but it is an easy thing to eliminate nonetheless.
The logon screen is very likely not using the same resolution setting as the desktop session.

Do things work correctly in a live USB session?

You *might* try deleting or moving/renaming your kscreen configurations (~/.local/share/kscreen/) and log out/reboot), though I don't *think* this will help in this situation.

You can see how to get monitor information as well as some basic xrandr usage information here: https://linuxconfig.org/how-to-confi...randr-in-linux
Seeing some extra details on your external monitor's current settings and capabilities might reveal useful info, and hopefully point to a solution.

If the OS is reporting the correct resolution output, then it seems that x11 somehow on your particular hardware or monitor needs an overscan adjustment or something along those lines.
Sure, it well could be a bug, but on old hardware, and with monitors of such vintage being notorious for not reporting EDID information to proper specs consistently, this isn't always easy to manage. An update could have revelaed such a bad EDID, perhaps.

Basically, there could be many causes, as well as many potential fixes, so it may take some digging. Hopefully not much.



Believe it or not, Wayland is not ignoring it, it is what is fixing things, since it is what xorg devs have all moved on to.
Maybe not today, for all, mind you.

It doesn't help that Plasma and multi-monitor support seem to be notoriously buggy/bad right now, no matter the display server.

Yes, I understand that Wayland is attempting to make life better. It may actually make life better for a user that uses a single desktop system at this time. However I have been using X11 for 25 years or so and I have several systems using it and in particular I have been using synergy and now barrier for 20+ years and it doesn't work with Wayland. I hope one day Wayland will better support interoperability with X11 displays as some systems don't have wayland.

The suggestion to delete the kscreen configurations helped to pinpoint where the issue is. It worked to resolve the issue, but only until the system was shut down and restarted. Then the problem was evident again. As I mentioned this was not an issue for the last couple of years and it became a problem I believe last week after some updates were applied. It appears to me that there is a bug now in the way kde is using the configuration data. The kscreen configs appear to be correct and work correctly until the system is restarted. I can repeat this process and duplicate the error repeatedly. Works until reboot. The kscreen configs are consistent with the configuration that works in Gnome. The login screen works correctly in all cases. This appears to be a recently introduced kde bug related to configuring the screens on startup.

I am unfortunately growing weary of Kubuntu and the decisions Ubuntu is making and I may have to go back to Gentoo to get the stability I am looking for. Maybe I'll try debian.