Okay, so..
I'm not sure if this is actually kscreenlocker, or if it's Kwin, or an entirely other component instead, or if this is an entirely unrelated bug.

I went ahead and turned off automatic lockscreen, so I wouldn't have to deal with being stuck on the lockscreen, however, now after coming back and waking the screen up from automatically turning off, the Plasma is completely unresponsive. I see the cursor change and react to open apps, but Plasma itself is unresponsive for a period, before reacting again. 

Monitor is a ViewSonic XG2405 if that has any relevance.

All of this does sound quite related.

A way to narrow it down is to manually lock the screen with meta+L without involving sleep/wake at all. When you manually lock and unlock, do you still see the issue?

Also, I'm guessing this is a single-screen desktop system, right?

(In reply to Nate Graham from comment #2)
> All of this does sound quite related.
> 
> A way to narrow it down is to manually lock the screen with meta+L without
> involving sleep/wake at all. When you manually lock and unlock, do you still
> see the issue?
> 
> Also, I'm guessing this is a single-screen desktop system, right? 

If I manually lock and unlock before the monitor turns off, I don't see an issue, no. Also, just to be clear, it's not the system going into sleep/hibernation, just the monitor turning off.

Yep, it is a single screen desktop.

Thanks. Does it happen on Wayland too, or only X11?

 i've the same issue && when i lock manually the screen with meta+L everything is OK.

it happen on Wayland as i am using wayland.

i was thinking that bug was related to my "resume kernel" setting or with my Graphics Processor unit but apparently it is not.

Operating System: EndeavourOS 
KDE Plasma Version: 6.0.2
KDE Frameworks Version: 6.0.0
Qt Version: 6.6.2
Kernel Version: 6.8.1-zen1-1-zen (64-bit)
Graphics Platform: Wayland
Processors: 12 × Intel® Core™ i7-9750H CPU @ 2.60GHz
Memory: 15.4 Gio of RAM
Graphics Processor: NVIDIA GeForce GTX 1650/PCIe/SSE2

For people affected, does the issue go away if you change your Plasma style to something other than "Breeze"? For example "Breeze Dark?" Not the global scheme or the color scheme; just the Plasma style.

> plasma style to something other than "Breeze"? For example "Breeze Dark?" Not the global scheme or the color
> scheme; just the Plasma style.

my plasma style it is "lightly" & it happens....

> plasma style to something other than "Breeze"? For example "Breeze Dark?" Not the global scheme or the color
> scheme; just the Plasma style.

my plasma style it is "lightly" & it happens....

The only way to overcome the problem is to " killall plasmashell && kstart plasmashell "

It happened on both Wayland and X11, yes.

I can't, currently, check whether switching the Plasma style "fixes" it, as I'm not near that machine, but will get back as soon as I've tried. :)

Well, changing the Plasma style didn't change anything for me either.

I'm honestly at a loss for how to really test this.

Likely a duplicate of https://bugs.kde.org/show_bug.cgi?id=485084

That looks like a different issue. This one looks more likely to be related to the odd network errors:

giu 26 08:26:49 betelgeuse kscreenlocker_greet[126137]: QMetaObject::invokeMethod: No such method ScreenLocker::AccessDeniedNetworkReply::error(QNetworkReply::NetworkError)

For anyone affected who sees those errors, are you using a non-default login screen theme, or are you using a remote URL for your avatar image, or are you on a network home directory or something? Is there *anything* network-related that might be unusual with respect to your setup that you can comment on?

Dear Bug Submitter,

This bug has been in NEEDSINFO status with no change for at least
15 days. Please provide the requested information as soon as
possible and set the bug status as REPORTED. Due to regular bug
tracker maintenance, if the bug is still in NEEDSINFO status with
no change in 30 days the bug will be closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

If you have already provided the requested information, please
mark the bug as REPORTED so that the KDE team knows that the bug is
ready to be confirmed.

Thank you for helping us make KDE software even better for everyone!

(In reply to Nate Graham from comment #13)
> That looks like a different issue. This one looks more likely to be related
> to the odd network errors:
> 
> giu 26 08:26:49 betelgeuse kscreenlocker_greet[126137]:
> QMetaObject::invokeMethod: No such method
> ScreenLocker::AccessDeniedNetworkReply::error(QNetworkReply::NetworkError)
> 
> For anyone affected who sees those errors, are you using a non-default login
> screen theme, or are you using a remote URL for your avatar image, or are
> you on a network home directory or something? Is there *anything*
> network-related that might be unusual with respect to your setup that you
> can comment on?

Nothing remote, and just the default lock screen. To be precise, it happens on both default, and non-default login themes.

I probably won't be much help in the future, as I've had to switch desktop. But I did a quick test on 6.1.2, and can confirm it still happens there.

From the output, it looks like it's the media controls on the lock screen that blocked the unlock request. It makes me wonder what was playing at the time, and through what application
It makes me wonder if the network stack hadn't fully woken yet and was being polled by the media widget, which hung waiting for the still sleeping service?

Setting to confirmed since the problem still happens for the OP

(In reply to TraceyC from comment #16)
> From the output, it looks like it's the media controls on the lock screen
> that blocked the unlock request. It makes me wonder what was playing at the
> time, and through what application
> It makes me wonder if the network stack hadn't fully woken yet and was being
> polled by the media widget, which hung waiting for the still sleeping
> service?
> 
> Setting to confirmed since the problem still happens for the OP

I usually have Spotify running at pretty much at all times, but as far as I remember, I actually did run a test with Spotify closed where it still happened. Also tried with the .deb(AUR) version and Flatpak version. However, I don't recall if I had say, Firefox open, with youtube, which would still work with the media play widget, yes?

I am also having issues with this, without any programs open. Issues started when updating to Plasma 6.1.

Hardware Information
  - 12th Gen Intel(R) Core(TM) i7-12700H (12+8) @ 4.70 GHz
  - Intel Iris Xe Graphics @ 1.40 GHz [Integrated]
  - NVIDIA GeForce RTX 3060 Mobile / Max-Q [Discrete]
- Software Information
  - Arch Linux x86_64
  - 6.9.10-arch1-1
  - sddm 0.21.0 (X11) 
  - KDE Plasma 6.1.3

(In reply to Antonio from comment #18)
> I am also having issues with this, without any programs open. Issues started
> when updating to Plasma 6.1.
> 
> Hardware Information
>   - 12th Gen Intel(R) Core(TM) i7-12700H (12+8) @ 4.70 GHz
>   - Intel Iris Xe Graphics @ 1.40 GHz [Integrated]
>   - NVIDIA GeForce RTX 3060 Mobile / Max-Q [Discrete]
> - Software Information
>   - Arch Linux x86_64
>   - 6.9.10-arch1-1
>   - sddm 0.21.0 (X11) 
>   - KDE Plasma 6.1.3

With this exact same log messaging?

MetaObject::invokeMethod: No such method ScreenLocker::AccessDeniedNetworkReply::error(QNetworkReply::NetworkError)
QMetaObject::invokeMethod: No such method ScreenLocker::AccessDeniedNetworkReply::error(QNetworkReply::NetworkError)
file:///usr/share/plasma/look-and-feel/org.kde.breeze.desktop/contents/lockscreen/MediaControls.qml:31:13: QML QQuickImage: Blocked request.

Or no?

(In reply to Nate Graham from comment #19)
> (In reply to Antonio from comment #18)
> > I am also having issues with this, without any programs open. Issues started
> > when updating to Plasma 6.1.
> > 
> > Hardware Information
> >   - 12th Gen Intel(R) Core(TM) i7-12700H (12+8) @ 4.70 GHz
> >   - Intel Iris Xe Graphics @ 1.40 GHz [Integrated]
> >   - NVIDIA GeForce RTX 3060 Mobile / Max-Q [Discrete]
> > - Software Information
> >   - Arch Linux x86_64
> >   - 6.9.10-arch1-1
> >   - sddm 0.21.0 (X11) 
> >   - KDE Plasma 6.1.3
> 
> With this exact same log messaging?
> 
> MetaObject::invokeMethod: No such method
> ScreenLocker::AccessDeniedNetworkReply::error(QNetworkReply::NetworkError)
> QMetaObject::invokeMethod: No such method
> ScreenLocker::AccessDeniedNetworkReply::error(QNetworkReply::NetworkError)
> file:///usr/share/plasma/look-and-feel/org.kde.breeze.desktop/contents/
> lockscreen/MediaControls.qml:31:13: QML QQuickImage: Blocked request.
> 
> Or no?

I tried running the same file as comment #0, but that locked the screen for the root user and didn't output that. Are the logs for the normal flow stored somewhere? I don't know where to locate it, sorry.

If this adds any value, when putting the pc to sleep, with the option of locking after wakeup, this problem doesn't happen. It also doesn't happen when locking with "super L" + "L". It only happens after automatic lock with any specified time (I set it to 1 minute for easy reproduction).

Also, ocasionally, the password input will never pop up and will have to reboot through tty3.

Important note (sorry I didn't include it earlier, I just noticed...).

This only happens when I am using only nvidia. In hybrid or integrated mode, this does not happen. Is that the case for other people that had the problem?

Another Nvidia on X11 user here. Here's my observation:
I get the described freeze/lag when the display is powered down but only when using the Nvidia proprietary driver on my work PC's GeForce GT 1030. Changing from proprietary driver to the nouveau driver solves the problem at the expense of everything else being generally laggy, nouveau being nouveau.
No freezing issues seen on my 2 personal computers with AMD graphics on Wayland.

Questions to ask others here are:
* Does this (still) affect AMD and Intel graphics? I see the bug submitter was on AMD.
* Does switching from nvidia proprietary to nouveau stop this from happening?

I can confirm this still happens in Plasma 6.1.4 on AMD, mesa 24.1.5

I can confirm that the bug still happens on Plasma version 6.1.4.
I also found a simple temporary workaround.

I commented out the entire Image object with id: albumArt, starting at line 31 in the file
/usr/share/plasma/look-and-feel/org.kde.breeze.desktop/contents/lockscreen/MediaControls.qml

This will remove the album art from the lock screen, but will also stop the bug from happening.

*** Bug 489846 has been marked as a duplicate of this bug. ***

*** Bug 483722 has been marked as a duplicate of this bug. ***

I experience the same issue.

Latest Arch Linux on Xorg, single monitor, open source Radeon drivers. 

Linux 6.10.4
kscreenlocker 6.1.4
xorg-server 21.1.13
xf86-video-amdgpu 23.0.0
sddm 0.21.0

Happens for me as well. Super irritating...it happens 8 out of 10 cases. What helps for me is to switch to console and pkill -f -9 kscreenlocker_greet. As far I remember, it started happening around Plasma 6.1. Maybe it is related, or not but, often monitor blinks multiple times and displays information that frequency is out of range. Sometimes only one screen is detected (monitor has to be enabled via Nvidia settings app), sometimes monitors display the same screen.

I have a two monitor setup.

Operating System: Fedora Linux 40
KDE Plasma Version: 6.1.4
KDE Frameworks Version: 6.5.0
Qt Version: 6.7.2
Kernel Version: 6.10.4-200.fc40.x86_64 (64-bit)
Graphics Platform: X11
Processors: 24 × AMD Ryzen 9 5900X 12-Core Processor
Memory: 62,7 GiB of RAM
Graphics Processor: NVIDIA GeForce RTX 3060/PCIe/SSE2
Manufacturer: Micro-Star International Co., Ltd.
Product Name: MS-7C91
System Version: 2.0

I just encountered this today on git master.

Well, this is kind of funny, but I can't replicate this anymore.
I installed F40 to test the "solution" in Comment 24, but that file doesn't exist on this install. 

X11
KDE Plasma Version: 6.1.4
KDE Frameworks Version: 6.5.0
Qt Version: 6.7.2
Mesa version: 24.1.5

Nevermind, it is happening again.
I've changed two things between then, and now, I moved the default panel to the top, switched it to "fit content", and then switched notification popups to the top right corner.

I am getting this error when using wallhaven wallpaper plugin, the network related action here is fetching a wallpaper from wallhaven, not even the initial wallpaper is fetched correctly, it fails everytime
here is the link to the plugin
https://github.com/Blacksuan19/plasma-wallpaper-wallhaven-reborn

(In reply to Ksenia Turek from comment #24)
> I can confirm that the bug still happens on Plasma version 6.1.4.
> I also found a simple temporary workaround.
> 
> I commented out the entire Image object with id: albumArt, starting at line
> 31 in the file
> /usr/share/plasma/look-and-feel/org.kde.breeze.desktop/contents/lockscreen/
> MediaControls.qml
> 
> This will remove the album art from the lock screen, but will also stop the
> bug from happening.

Nope. that didn't help. And this is happening regardles of the album art being displayed or not (for me it's never showing).

I am also having this issue, except that sometimes the system also locks up after logging in after booting.

I've also been having monitor troubles ever since Plasma 6.1. https://bugs.kde.org/show_bug.cgi?id=489457

There's definitely some kind of bug that has been introduced around that time, but I'm at a loss on what it could be.

Annoying because I love Plasma, and I don't want to switch to a different DE just for this issue.

How do I go about getting the list of commits that happened between versions 6.0 and 6.1?

Same here
Manjaro Linux
KDE 6.1.5
amdgpu
X11
After the system goes to hibernate, (hibernate works as it should, enough swap is there also) the system randomize freeze. 
Mean restore from hibernate there isn't a sddm-greeter.
The system either starts only with a black screen or it shows a "snapshot" of the hibernate, you can see that because the clock isn't running.
There is no keyboard or mouse. I can't use any key to switch to tty and restart the sddm session manually 
That issue is there since the update to plasma 6 with the 5th version everything works as it should

If anyone can reproduce this, can I have output of "journalctl --user -r" after this happens.

(In reply to David Edmundson from comment #38)
> If anyone can reproduce this, can I have output of "journalctl --user -r"
> after this happens.

Here's mine:

	Oct 12 01:35:49 FredArch kscreenlocker_greet[790136]: Failed to create RHI (backend 2)
	Oct 12 01:35:49 FredArch kscreenlocker_greet[790136]: QRhiGles2: Context is lost.
	Oct 12 01:35:49 FredArch kscreenlocker_greet[790136]: Failed to create RHI (backend 2)
	Oct 12 01:35:49 FredArch kscreenlocker_greet[790136]: QRhiGles2: Context is lost.
	Oct 12 01:35:49 FredArch kscreenlocker_greet[790136]: Graphics device lost, cleaning up scenegraph and releasing RHI
	Oct 12 01:35:49 FredArch kscreenlocker_greet[790136]: QRhiGles2: Context is lost.
	Oct 12 01:35:49 FredArch kscreenlocker_greet[790136]: Graphics device lost, cleaning up scenegraph and releasing RHI
	Oct 12 01:35:49 FredArch kscreenlocker_greet[790136]: QRhiGles2: Context is lost.
	Oct 12 01:35:36 FredArch kded6[2061]: colord: EDID ICC Profile already exists "/home/frederick/.local/share/icc/edid-8d55884d804292953dcbc6158f7e970c.icc"
	Oct 12 01:35:36 FredArch kded6[2061]: colord: EDID ICC Profile already exists "/home/frederick/.local/share/icc/edid-46a82c48dfb431b7ef4ae8d0e4834d17.icc"
	Oct 12 01:35:36 FredArch kded6[2061]: colord: Setting X atom (id: 1 ) "_ICC_PROFILE_1" on output: "DP-3"
	Oct 12 01:35:36 FredArch kded6[2061]: colord: Failed to register device: "device id 'xrandr-U2790B-<serial no.>' already exists"
	Oct 12 01:35:36 FredArch kded6[2061]: colord: Setting X atom (id: 0 ) "_ICC_PROFILE" on output: "HDMI-0"
	Oct 12 01:35:31 FredArch kded6[2061]: colord: Failed to register device: "device id 'xrandr-LG Electronics-LG ULTRAFINE-<serial no.>' already exists"

Operating System: Arch Linux 
KDE Plasma Version: 6.2.0
KDE Frameworks Version: 6.6.0
Qt Version: 6.7.3
Kernel Version: 6.10.10-arch1-1 (64-bit)
Graphics Platform: X11

I'm not able to reproduce with Wayland or X11 on git-master FWIW

(In reply to TraceyC from comment #40)
> I'm not able to reproduce with Wayland or X11 on git-master FWIW

I am seeing this too although its random and happens with Nvidia GPU and AMD Gpu.

I see this too on Alienware R14, ubuntu 24.04 and kde plasma 6.2. It has a dual 4k monitor setup, nvidia gfx and AMD cpu. I'm on Neon User, new install. Let me know if you need more details.

(In reply to Dennis from comment #42)
> I see this too on Alienware R14, ubuntu 24.04 and kde plasma 6.2. It has a
> dual 4k monitor setup, nvidia gfx and AMD cpu. I'm on Neon User, new
> install. Let me know if you need more details.

On wayland.

I think I might  have opened a duplicate here : https://bugs.kde.org/show_bug.cgi?id=494927

The difference is that I (and other people, apparently) have a specific line repeated in logs, when trying (without success) to unlock :
file:///usr/share/plasma/shells/org.kde.plasma.desktop/contents/lockscreen/LockScreenUi.qml:280: TypeError: Property 'respond' of object length is not a function

Bug 494927 doesn't look like a duplicate. The error messages are different. The symptoms are also subtly different.

*** Bug 494529 has been marked as a duplicate of this bug. ***

(In reply to TraceyC from comment #45)
> Bug 494927 doesn't look like a duplicate. The error messages are different.
> The symptoms are also subtly different.

I checked my journalctl --user and I found this

Oct 22 22:16:15 MyArchGamingPC kscreenlocker_greet[71014]: Graphics device lost, cleaning up scenegraph and releasing RHI
Oct 22 22:16:15 MyArchGamingPC kscreenlocker_greet[71014]: QRhiGles2: Context is lost.
Oct 22 22:16:04 MyArchGamingPC kscreenlocker_greet[71014]: Graphics device lost, cleaning up scenegraph and releasing RHI
Oct 22 22:16:04 MyArchGamingPC kscreenlocker_greet[71014]: QRhiGles2: Context is lost.
Oct 22 22:16:04 MyArchGamingPC kscreenlocker_greet[71014]: pam_systemd_home(kde:auth): New sd-bus connection (system-bus-pam-systemd-home-71014) opened.

So no the bug report I created Bug 494927 was a duplicate. Just one thing I am not sure If I saw I only experience this on x11, works fine on wayland. Also all of the time it takes is max 20 seconds for the screen to go back to normal, not a minute. Also one big difference is it doesn't happen at all when I lock using meta+L only when the my pc locks at any time when the screen is off.

*** Bug 495388 has been marked as a duplicate of this bug. ***

I re-tested at Nate's request
nVidia GPU Plasma 6.1.5       - cannot reproduce with Wayland or X11
AMD GPU Plasma git-master  - cannot reproduce with Wayland or X11

This is still happening for me

Output from journalctl right after:
```
okt 31 10:17:43 cachyos kscreenlocker_greet[17494]: pam_unix(kde:auth): authentication failure; logname=user uid=1000 euid=1000 tty= ruser= rhost=  user=user
okt 31 10:17:38 cachyos org_kde_powerdevil[1355]: dh=Display_Handle[i2c-4: fd=27], Keeping adjusted sleep multiplier 2,00 for SE_POST_WRITE or SE_POST_SAVE_SETTINGS
okt 31 10:17:37 cachyos org_kde_powerdevil[1355]: Executed 1 registered callbacks.
okt 31 10:17:37 cachyos org_kde_powerdevil[1355]: Emitting DDCA_Display_Status_Event( 10917.059:  DDCA_EVENT_DPMS_AWAKE, card0-DP-1, dref: Display_Ref[bus /dev/i2c-4], io_path:/dev/i2c-4]
okt 31 10:17:35 cachyos org_kde_powerdevil[1355]: stabilized_connector_names required 1 extra calls to get_sysfs_drm_connector_names()
okt 31 10:17:29 cachyos kscreenlocker_greet[17494]: file:///usr/share/plasma/shells/org.kde.plasma.desktop/contents/lockscreen/MediaControls.qml:31:13: QML Image: Blocked request.
okt 31 10:17:29 cachyos kscreenlocker_greet[17494]: qt.gui.imageio: libpng warning: iCCP: known incorrect sRGB profile
okt 31 10:17:28 cachyos kscreen_backend_launcher[1442]: kscreen.xrandr: Emitting configChanged()
okt 31 10:17:28 cachyos plasmashell[1273]: qt.gui.imageio: libpng warning: iCCP: known incorrect sRGB profile
okt 31 10:17:28 cachyos plasmashell[1273]: qt.gui.imageio: libpng warning: iCCP: known incorrect sRGB profile
okt 31 10:17:28 cachyos kscreen_backend_launcher[1442]: kscreen.xrandr: Output 87 : connected = false , enabled = false
```
CachyOS
KDE Plasma Version: 6.2.2
KDE Frameworks Version: 6.7.0
Qt Version: 6.8.0
Kernel Version: 6.11.5
Graphics Platform: X11