Bug 500316

Summary: Window header does not scale with X11
Product: [Plasma] kwin Reporter: TripleCamera
Component: X11 IntegrationAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED WORKSFORME    
Severity: normal CC: nate
Priority: NOR Keywords: X11-only
Version First Reported In: 6.3.0   
Target Milestone: ---   
Platform: Arch Linux   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: System Settings with X11
System Settings with Wayland
System Settings with X11, after updating global scale factor

Description TripleCamera 2025-02-18 13:30:38 UTC
SUMMARY
Window header does not scale with X11. This affects KDE apps, but not apps like Chrome and Firefox.

STEPS TO REPRODUCE
1. Set global scale to over 100%.
2. Login with Plasma (X11), open System Settings.
3. Login with Plasma (Wayland), open System Settings.

OBSERVED RESULT
The window header does not scale with X11, and does scale with Wayland.

EXPECTED RESULT
The window header does scale with both X11 and Wayland.

SOFTWARE/OS VERSIONS
KDE Plasma Version: 6.3.0
KDE Frameworks Version: 6.11.0
Qt Version: 6.8.2

ADDITIONAL INFORMATION
Comment 1 TripleCamera 2025-02-18 13:32:11 UTC
Created attachment 178517 [details]
System Settings with X11
Comment 2 TripleCamera 2025-02-18 13:34:01 UTC
Created attachment 178519 [details]
System Settings with Wayland
Comment 3 Vlad Zahorodnii 2025-02-18 13:56:49 UTC
Please post the output of

   xrdb -query
Comment 4 Nate Graham 2025-02-18 15:10:00 UTC
You have to restart the system or kwin_x11 after changing the global scale factor on X11; it doesn't take effect instantly the way it does on Wayland.

IIRC there's supposed to be a message on the page that tells you this. Did no such message appear after you changed the scale?
Comment 5 TripleCamera 2025-02-20 07:09:49 UTC
(In reply to Vlad Zahorodnii from comment #3)
> Please post the output of
> 
>    xrdb -query

$ xrdb -query
Xcursor.size:   60
Xcursor.theme:  breeze_cursors
Xft.antialias:  1
Xft.dpi:        96
Xft.hinting:    1
Xft.hintstyle:  hintslight
Xft.rgba:       rgb
Comment 6 TripleCamera 2025-02-20 07:24:47 UTC
(In reply to Nate Graham from comment #4)
> You have to restart the system or kwin_x11 after changing the global scale
> factor on X11; it doesn't take effect instantly the way it does on Wayland.
> 
> IIRC there's supposed to be a message on the page that tells you this. Did
> no such message appear after you changed the scale?

I set global scale factor to 250% back in Plasma 5, far before that bug appeared. When I upgraded to Plasma 6, I switched to Wayland since it became the default option. The first time I noticed the bug was when I changed back to X11, on Plasma 6.2.?. After that, this bug appeared every time I switched to X11, so it's obviously a bug.

Besides, I just tried to change the scale, and no, there was no message telling me this.
Comment 7 TripleCamera 2025-02-20 07:30:41 UTC
Wait, I just set the global scale factor to 100% and then back to 250%, then the bug disappears.

That is so strange!
Comment 8 TripleCamera 2025-02-20 07:31:38 UTC
Created attachment 178625 [details]
System Settings with X11, after updating global scale factor
Comment 9 Vlad Zahorodnii 2025-02-20 12:18:01 UTC
(In reply to TripleCamera from comment #5)
> (In reply to Vlad Zahorodnii from comment #3)
> > Please post the output of
> > 
> >    xrdb -query
> 
> $ xrdb -query
> Xcursor.size:   60
> Xcursor.theme:  breeze_cursors
> Xft.antialias:  1
> Xft.dpi:        96
> Xft.hinting:    1
> Xft.hintstyle:  hintslight
> Xft.rgba:       rgb

Xft.dpi is wrong. Make sure that you have things such as xsettingsd and so on installed. Also check `forceFontDPI` in `[General]` in `~/.config/kcmfonts`
Comment 10 TripleCamera 2025-02-22 13:29:40 UTC
(In reply to Vlad Zahorodnii from comment #9)
> Xft.dpi is wrong. Make sure that you have things such as xsettingsd and so
> on installed. Also check `forceFontDPI` in `[General]` in
> `~/.config/kcmfonts`

I just ran `xrdb -query` again, and the values changed:
$ xrdb -query
Xcursor.size:   60
Xcursor.theme:  breeze_cursors
Xft.antialias:  1
Xft.dpi:        240
Xft.hinting:    1
Xft.hintstyle:  hintslight
Xft.rgba:       rgb

It seems that changing the global scale factor in System Settings updated the DPI config and made it correct.
Comment 11 TraceyC 2025-02-24 17:58:25 UTC
Adding the x11-only keyword
Comment 12 Bug Janitor Service 2025-03-11 03:47:28 UTC
๐Ÿ›๐Ÿงน โš ๏ธ This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information, then set the bug status to REPORTED. If there is no change for at least 30 days, it will be automatically closed as RESOLVED WORKSFORME.

For more information about our bug triaging procedures, please read https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging.

Thank you for helping us make KDE software even better for everyone!
Comment 13 TripleCamera 2025-03-12 02:29:02 UTC
It seems that this bug can be easily fixed by updating the Global Scale Factor in System Settings. Should I close this bug now?

Here are two possible reasons not to close this bug now:
1. An update broke the backward compatibility of Plasma config about Global Scale Factor. Users have to re-assign the Global Scale Factor to make it work correctly, which may bring inconvenience.
2. There *should* be a message telling you to restart the system when changing Global Scale Factor, but there is not.
Comment 14 Bug Janitor Service 2025-03-27 03:46:44 UTC
๐Ÿ›๐Ÿงน โš ๏ธ This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information, then set the bug status to REPORTED. If there is no change for at least 30 days, it will be automatically closed as RESOLVED WORKSFORME.

For more information about our bug triaging procedures, please read https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging.

Thank you for helping us make KDE software even better for everyone!
Comment 15 Bug Janitor Service 2025-04-11 03:47:04 UTC
๐Ÿ›๐Ÿงน This bug has been in NEEDSINFO status with no change for at least 30 days. Closing as RESOLVED WORKSFORME.