Bug 484573

Summary:	Some bold mono fonts are actually "bolder" than normal fonts on Wayland.
Product:	[Applications] kate	Reporter:	Mosklia <Sparky_14145>
Component:	general	Assignee:	KWrite Developers <kwrite-bugs-null>
Status:	RESOLVED FIXED
Severity:	normal	CC:	christoph
Priority:	NOR
Version First Reported In:	24.02.1
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:
Attachments:	Screenshot when using WenQuanYi Micro Hei Mono font

Description Mosklia 2024-03-27 05:22:42 UTC

Created attachment 167832 [details]
Screenshot when using WenQuanYi Micro Hei Mono font

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SUMMARY
Some bold mono fonts are actually "bolder" than normal fonts.
Though reported in Plasma 6, this can be observed on Plasma 5 if you use Wayland. Cannot be observed on X11.
Konsole does also have this problem.

STEPS TO REPRODUCE
1. Open Kate
2. Select some bold mono fonts as editor font (Not all, the fonts I know can reproduce are WenQuanYi Micro Hei Mono and WenQuanYi Zen Hei Mono.)
3. You may see that words highlighted as bold are "bolder", or wider than the others.

OBSERVED RESULT
words highlighted as bold are "bolder", or wider than the others.

EXPECTED RESULT
All words should be of the same width.

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: 
Archlinux 6.8.1-arch1-1 (64 bit)
KDE Plasma Version: 6.0.2
KDE Frameworks Version: 6.0.0
Qt Version: 6.6.2

ADDITIONAL INFORMATION
DroidSansMono Nerd Fonts seem to have problems too. When using DroidSansMono Nerd Font and DroidSansMono Nerd Font Mono, the highlighted words have no visual difference than the others. When using DroidSansMono Nerd Fond Proto the highlighted words are wider. Other mono fonts seems to be correct.

When "Show mono fonts only" is on, WenQuanYi fonts are not shown. But DroidSansMono Nerd Fonts are shown.

Comment 1 Christoph Cullmann 2024-03-27 20:07:10 UTC

Have you some scale factor set for the display?

Comment 2 Mosklia 2024-03-28 01:44:02 UTC

(In reply to Christoph Cullmann from comment #1)
> Have you some scale factor set for the display?

2 monitor, one for 150% and one for 135%. Both can reproduce this.

Comment 3 Christoph Cullmann 2024-04-10 20:10:23 UTC

https://invent.kde.org/frameworks/ktexteditor/-/commit/2ab959985587e1f55fd669a3001bb48d2816c382

perhaps this fixes it, if not, one must report it upstream to Qt, as I see no way that we can alter that in the KDE stack.