Bug 497797

Summary: Firefox font rendering more blurry on KDE Plasma compared to GNOME
Product: [Applications] systemsettings Reporter: NW <nw9165-jjnfov5mav>
Component: kcm_fontsAssignee: Plasma Bugs List <plasma-bugs-null>
Status: RESOLVED WORKSFORME    
Severity: normal CC: ilikefoss, john.kizer
Priority: NOR    
Version First Reported In: 6.2.5   
Target Milestone: ---   
Platform: unspecified   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:
Attachments: Firefox in a Neon VM next to Firefox in an Ubuntu VM

Description NW 2024-12-22 21:25:06 UTC
Hi,

The Firefox font rendering is more blurry on KDE Plasma compared to GNOME.

When using a KDE Plasma based distro (such as the latest Fedora KDE for example) with regular OS font settings, the font rendering in Firefox is somewhat blurry.

When using a GNOME based distro (such as the latest regular Fedora for example) with regular OS font settings, the font rendering in Firefox is noticeably sharper.

How can this be? And how can it be fixed?

No setting in "KDE Plasma System Settings > Text & Fonts > Fonts" seems to change this.
Comment 1 John Kizer 2025-01-02 03:23:25 UTC
Hi - are you able to share screenshots of what you're observing on each system? Are the screen scaling settings equivalent on both systems? And, could you please share your system information as requested in the bug template (included below)?

Linux/KDE Plasma: 
KDE Plasma Version: 
KDE Frameworks Version: 
Qt Version: 

Thanks!
Comment 2 Bug Janitor Service 2025-01-17 03:47:52 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 3 NW 2025-01-25 22:27:42 UTC
It seems to be distro-agnostic and is happening on both the latest Arch Linux as well as Fedora versions for example and also happens at 100% scaling.

Linux: Latest Arch Linux or Fedora and others
KDE Plasma Version: 6.2.5
KDE Frameworks Version: 6.10.0
Qt Version: 6.8.1
Kernel Version: 6.12.10
Graphics Platform: Wayland
Firefox Version: Latest

Only Firefox is affected. And it only happens when using KDE Plasma. Not when using GNOME.

Chromium is also not affected.
Comment 4 NW 2025-01-25 22:31:09 UTC
No screenshots attached because it can easily be tested by booting a KDE Plasma based distro and GNOME based distro (such as latest Fedora KDE and Fedora GNOME) in a VM next to each other to compare it.
Comment 5 John Kizer 2025-01-26 03:18:59 UTC
Hi - I'd like to ask to see how things are showing up on your screen, because I cannot personally tell a qualitative difference between Firefox in a Neon VM and Firefox in an Ubuntu Desktop VM. I'll attach a screenshot from across two VMs as an example.
Comment 6 John Kizer 2025-01-26 03:19:29 UTC
Created attachment 177686 [details]
Firefox in a Neon VM next to Firefox in an Ubuntu VM
Comment 7 Bug Janitor Service 2025-02-10 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 8 Bug Janitor Service 2025-02-25 03:46:57 UTC
๐Ÿ›๐Ÿงน This bug has been in NEEDSINFO status with no change for at least 30 days. Closing as RESOLVED WORKSFORME.
Comment 9 John 2025-02-25 08:32:26 UTC
Firefox fonts always seemed a bit blurry to me on Plasma, but I don't have Gnome or Windows to compare.
And I'm not sure pictures from VMs are such a good idea for this problem as VMs probably cannot read and pass all the screen details to the renderers inside, besides drivers issues.'
If anyone has good internet and can download a distro with Gnome and boot it, then take some printscreens, it would be great!
I don't think KDE developers have time for everything, so at least we can do this part.
I would do it myself, but at this moment I'm only on a limited traffic mobile connection.