Lately, I’ve not been getting font antialiasing in some applications after startup. It works correctly in Qt applications, but not in GTK applications or Wine applications. If I disable and reenable antialiasing in the KDE settings, it starts working in those applications (after restarting them), but only until I log out and log back in. If I run xrdb -query | grep Xft.antialias, I get Xft.antialias: 0, whereas on another on another computer which does not have this problem I get Xft.antialias: 1. If I run echo 'Xft.antialias: 1' | xrdb -merge - that resolves it but, again, only temporarily.
Operating System: openSUSE Tumbleweed 20230921
KDE Plasma Version: 5.27.8
KDE Frameworks Version: 5.110.0
Qt Version: 5.15.10
Kernel Version: 6.5.4-1-default (64-bit)
Graphics Platform: X11
Processors: 16 × AMD Ryzen 7 5800X 8-Core Processor
Memory: 62.7 Gibyte of RAM
Graphics Processor: NVIDIA GeForce RTX 2080 Ti/PCIe/SSE2
Manufacturer: ASUS
Install dconf-editor, start it and search for “font-antialiasing”.
Default is “greyscale”, set it to “rgba” and you should be done.
When trying to start that via the .desktop file I get and error notification saying “Invalid object path: /ca/desrt/dconf-editor”, though it does start if I launch it via the terminal.
Anyway, changing that didn’t do anything. I didn’t expect it to though, if that setting was used presumably text should already have been antialiased when it was set to grayscale.
The problem seems to be due to XftAntialias=false being in .config/kdeglobals. It seems like the Plasma settings doesn’t set that properly. Sometimes often toggling the antialiasing checkbox in the Plasma doesn’t set that setting, or it sets it to the opposite of what it’s supposed to.
I assume you have set antialiasing, subpixel rendering and hinting in KDE systemsettings.
For me these values were not used by GTK applications (Tumbleweed here as well).
You can set “font-rgba-order” and “font-hinting” using dconf-editor as well and you can look at the changes immediately after you hit the “Apply” button (dconf-editor is a GTK app), at least this is how it works here. May be the values are superseded by Xft values, I have not set these at all.
I am on plasma-wayland, but I doubt this makes a difference in font appearance.
I am on plasma-wayland, but I doubt this makes a difference in font appearance
It does actually. If I switch over to Wayland, GTK applications follow the dconf setting. But under X11, they ignore it and use the Xft settings.