SUMMARY When plasma 6 is installed it automatically adjusts display scale to 125%. But fonts looks blurry and not usable. Previously, in plasma 5 i used to fix it using Force FONT DPI in font settings, it's no longer there anymore. [POC] https://imgur.com/lG7DtoX [Font Settings] https://imgur.com/UjpLvLJ SOFTWARE/OS VERSIONS Operating System: Arch Linux KDE Plasma Version: 6.0.1 KDE Frameworks Version: 6.0.0 Qt Version: 6.6.2 Kernel Version: 6.7.8-arch1-1 (64-bit) Graphics Platform: Wayland Processors: 8 × Intel® Core™ i5-9300H CPU @ 2.40GHz Memory: 15.3 GiB of RAM Graphics Processor: Mesa Intel® UHD Graphics 630 Manufacturer: Dell Inc.
Can confirm, it also happens on my work machine. I did not use to force the font's DPI manually, but font rendering was _way_ better under Plasma 5.2x.xx. I always used Wayland on my work machine, with my external monitor at 125% scaling. Something definitely changed in the move to Plasma 6/Qt6. However, on the integrated display where I set the scale to 200% the font rendering has not changed a bit. Still as crisp as ever. What's more, the font hinting options of 'slight' and 'medium' seem completely broken: the baseline of some glyphs do not line up at all. I'll attach a screenshot in a bit. I use the 'SF Pro Display' font from Apple, obtained through https://aur.archlinux.org/packages/apple-fonts All my fonts' base size is 10pt, except for the 'small text' option which is at 8pt. System info from Settings: Operating System: Arch Linux KDE Plasma Version: 6.0.1 KDE Frameworks Version: 6.0.0 Qt Version: 6.6.2 Kernel Version: 6.7.8-arch1-1 (64-bit) Graphics Platform: Wayland Processors: 12 × Intel® Core™ i7-8850H CPU @ 2.60GHz Memory: 31,0 GiB of RAM Graphics Processor: Mesa Intel® UHD Graphics 630 Manufacturer: Dell Inc. Product Name: Precision 5530
Created attachment 166589 [details] Comparison shots of the SF Pro font with different hinting levels. (In reply to devillelethibault from comment #1) > Can confirm, it also happens on my work machine. I did not use to force the > font's DPI manually, but font rendering was _way_ better under Plasma > 5.2x.xx. I always used Wayland on my work machine, with my external monitor > at 125% scaling. Something definitely changed in the move to Plasma 6/Qt6. > However, on the integrated display where I set the scale to 200% the font > rendering has not changed a bit. Still as crisp as ever. > > What's more, the font hinting options of 'slight' and 'medium' seem > completely broken: the baseline of some glyphs do not line up at all. I'll > attach a screenshot in a bit. As promised, here are comparison shots of both the 'SF Pro Display' font and the 'SF Pro' font (which is slightly thinner and straighter). Look especially at the page titles: the 'n' in 'Fonts' does not line up its baseline to the other characters, and on some hinting levels the horizontal spacing between characters seem to overlap.
Created attachment 166590 [details] Comparison shots of the SF Pro Display font with different hinting levels.
Created attachment 166598 [details] Horizontal glyph placement issues. A small update: setting the sub-pixel rendering to "Vertical RGB" greatly improves vertical legibility on my external monitor (but I did not need to do it in Plasma 5.2x ...). However, the fonts' horizontal spacing issues are only exacerbated by the new sub-pixel layout.
*** This bug has been marked as a duplicate of bug 479891 ***