SUMMARY Plasma doesn't respect Sub-pixel rendering for system tray and desktop. I want Sub-pixel rendering turned off everywhere. It was always turned off till Frameworks 5.101.0 or Plasma 5.26.4, I'm not shure. Now in the settings Sub-pixel rendering is turned off but in system tray. My calendar, clock, keyboard layout, network applet, etc icons and menus are all with Sub-pixel rendering tuned on. It can be disabled only if I remove an aplet and add it again until the system restarts and then it's turned on again. Icons, files and shortcuts on the desktop are all with Sub-pixel rendering turned as well. If I create a new file or folder on the desktop, it's with Sub-pixel rendering turned off and I can put it side by side with others files which are with RGB on so I can have files with Sub-pixel rendering turned off and on at the same time and in the same place. Sub-pixel rendering works as expected everywhere inside KDE / QT applications. STEPS TO REPRODUCE 1. Start plasma 2. 3. OBSERVED RESULT Plasma doesn't respect Sub-pixel rendering for system tray and desktop files, folders and shortcuts. EXPECTED RESULT Plasma should respect Sub-pixel rendering for system tray and desktop files, folders and shortcuts. SOFTWARE/OS VERSIONS Linux/KDE Plasma: Arch Linux KDE Plasma Version: 5.26.4 KDE Frameworks Version: 5.101.0 Qt Version: 5.15.7
Now I upgraded a second PC and the problem is there as well so everyone shoud have the same problem.
Just realized the task switcher's list is affected as well.
Here's a task switcher screenshot. See the text: https://i.imgur.com/sNXg9kv.png You can also see the clock and the keyboard layout.
I'm sorry, on this screenshot the keyboard layout is fine but the cock it isn't. You can zoom in and see the RGB pixels.
Created attachment 154627 [details] RGB Clock Zoomed image of the clock. RGB is clearly visible and it should be turned off.
The same issue occurs for me: SOFTWARE/OS VERSIONS Linux/KDE Plasma: Arch Linux KDE Plasma Version: 5.26.4 KDE Frameworks Version: 5.101.0 Qt Version: 5.15.7
Not only the subpixel rendering is force enabled but the hinting settings are ignored as well (no hinting applied). And not only the tray is affected but also the Task Manager, KRunner, Application Menu, Task Switcher, Digital Clock and probably some more widgets as well.
I didn't notice KRunner, thank you. However, I'm using the legacy start menu and it's ok.
One more finding: If I issue kquitapp5 plasmashell && kstart5 plasmashell, the opened apps in the panel are with RGB sub-pixel rendering turned on. Only a restart fixes it.
Plasma 5.26.5 - the problem is still here. Even tweaking /etc/fonts/local.conf doesn't help.
Nothing should have changed in Plasma recently, so it's highly likely to have been a regression caused by Qt or fontconfig. What distro are you affected folks using, and what version of the fontconfig package do you have? And can you all paste the output of running `grep Xft ~/.config/kdeglobals` in a terminal window? Thanks!
Another option is that the issue was caused by https://invent.kde.org/frameworks/plasma-framework/-/commit/4d5ff1dc5171af5815f4b8d7f258cad1f9425240, which removed a workaround for an issue that was fixed in Qt. By doing that, now everyone is getting their text rendered Text.NativeRendering in Qt, as opposed to sometimes using Text.QtRendering for fractional scale factors. So maybe Text.NativeRendering doesn't respect this setting like it should and this exposed a pre-existing Qt bug for users of fractional scale factors. Are all of you using a scale factor other than 100%, 200% or 300%?
(In reply to Nate Graham from comment #12) ``` $ grep Xft ~/.config/kdeglobals XftAntialias=true XftHintStyle=hintslight XftSubPixel=none ``` Global scale factor: 100%
(In reply to Felis from comment #13) > (In reply to Nate Graham from comment #12) Distro: Manjaro, fontconfig 2.14.1. I don't remember what if anything has changed in the past month but now the issue persists only in some places, namely KRunner's input field and Task Switcher's window list (I use Compact) and it disappears after some time in the latter.
(In reply to Nate Graham from comment #11) > Nothing should have changed in Plasma recently, so it's highly likely to > have been a regression caused by Qt or fontconfig. > > What distro are you affected folks using, and what version of the fontconfig > package do you have? > > And can you all paste the output of running `grep Xft ~/.config/kdeglobals` > in a terminal window? > > Thanks! grep Xft ~/.config/kdeglobals XftAntialias=true XftHintStyle=hintmedium XftSubPixel=none Arch Linux, fontconfig 2.14.1-2. I don't use any other global scale factor than 100%.
(In reply to Nate Graham from comment #11) > what version of the fontconfig > package do you have? Downgrading to a lower fontconfig version doesn't help at all.
Ok, so if none of you are using fractional scaling, it's probably not an issue caused by https://invent.kde.org/frameworks/plasma-framework/-/commit/4d5ff1dc5171af5815f4b8d7f258cad1f9425240. Could be a Qt issue or a fontconfig issue. What fontconfig version did you downgrade to? If it's the fontconfig issue I'm thinking of, you might need to go to 2.14.0 or earlier.
Yes, I don't use fractional scaling at all. I downgraded to fontconfig 2.13.96 and there's no change.
Okay so it's not fontconfig, and it's not https://invent.kde.org/frameworks/plasma-framework/-/commit/4d5ff1dc5171af5815f4b8d7f258cad1f9425240. It could be some other issue we caused (but how?) or a Qt bug that was introduced with an update. Did any of you also get distro updates for your Qt packages around when this started happening?
I really don't remember, sorry :(
Created attachment 155382 [details] Only the UI elements highlighted in red are respecting my setting "Sub-pixel rendering: None" For me it's not just the Plasma shell, but rather most UI elements within Firefox and KDE apps keep using subpixel rendering. I'm on a freshly installed and fully updated Kubuntu 22.04. I originally posted about this issue here and have attached more screenshots there showing the issue: https://www.reddit.com/r/kde/comments/10du9dd/cant_fully_disable_subpixel_font_rendering/ I can try my unupdated Kubuntu 22.04.1 ISO and will comment again in case it works there as expected.
I did two tests by booting the live images of current Neon user and Kubuntu 22.10. - Neon live-image: (Plasma 5.26.5, Frameworks 5.101, Qt 5.15.8) Can reproduce the bug. By default, sub-pixel rendering is turned off in the font settings. But nevertheless I can see in a screenshot that sub-pixel rendering is used in the text of the clock applet in the systray! For text in Kickoff and KDE apps (tested Systemsettings, Dophin, Window decoration), everything seems to be correct (no sub-pixel rendering). However, Firefox (GTK) uses sub-pixel rendering in its UI texts! - Kubuntu 22.10: (Plasma 5.25.5, Frameworks 5.98, Qt 5.15.6) Bug in the Plasma panel is not there. By default, sub-pixel rendering is turned on. If I turn it off in the font settings (and restart Plasma session), even the clock applet text is correctly rendered without sub-pixel rendering. For anything else, results are the same as within Neon: KDE apps correct, Firefox (GTK) "wrong".
Using the unupdated Kubuntu 22.04.1 live iso didn't change things, but I made a bizarre discovery. Even with the default setting to enable RGB subpixel rendering, the UI elements of System Settings from the attachment I uploaded are still rendered with grayscale on my machine. So it seems the setting is entirely ineffectual on Kubuntu 22.04 (without any backports repo)
It occurs it's a very serious problem.
Created attachment 155410 [details] Disks & Devices problem Here's more info about additional problem area. As you can see, sub-pixel rendering is turned off everywhere in the widget but for "Disk & Device in the upper left corner it isn't.
Unfortunately the bug exists in Plasma 5.27 Beta as well.
Plasma 5.27 - still here.
Created attachment 156315 [details] Font setting's hinting preview render under different hinting settings are the same Not sure if this is related, but hinting is also not respected. No matter which level you choose, it stays at "slight". A quick way to check: see the hinting preview in the font setting, it's all the same for all hinting levels.
Don't know why I was CCed, but I don't really have any idea.
It's sad but the bug is still here in Plasma 5.27.1.
Created attachment 156807 [details] krunner-forced-subpixel-rendering.png I wanted to report this for KRunner 5.27.1 (and earlier), but I guess that would duplicate this bug. Attaching screenshot.
Plasma 5.27.2 - the bug is still here.
Plasma 5.27.3 - the bug is still here.
Mozo, I'm afraid these kinds of comments are not really helpful. See https://community.kde.org/Get_Involved/Issue_Reporting#Have_realistic_expectations.
And nobody cares for such a big problem? For real??? It's still here in the latest Plasma release.
I want to ask - granted nobody cares, should we have the option to disable Sub-pixel rendering in Plasma 6 at all?
@mozo I hate subpixel rendering and would like to disable it all over KDE and everywhere else (GTK, etc).
@phd I hate it too but for the moment Plasma is the only DE where you can't disable it... It's a mess and I really can't understand how it's possible in 21st century a to have a DE with such ridiculous bug and it's actually a LTS release...
Interestingly, on Plasma 6 beta 1 I have a somewhat inverse problem. Mostly subpixel rendering is OFF as it should, but *some* software like tastenbrett (the on-screen keyboard visualization written in QML) have subpixel rendering ON. Operating System: Arch Linux KDE Plasma Version: 5.90.90 KDE Frameworks Version: 5.246.0 Qt Version: 6.6.1 Kernel Version: 6.6.3-arch1-1 (64-bit) Graphics Platform: X11 Processors: 8 × Intel® Core™ i7-6700HQ CPU @ 2.60GHz Memory: 15.6 GiB of RAM Graphics Processor: NVIDIA GeForce GTX 970M/PCIe/SSE2
There was hopes it will be fixed in Plasma 6...