Bug 494790

Summary:	Qt-6.8.0 makes Kate/Kwrite editor fonts invisible
Product:	[Applications] kate	Reporter:	l33tmmx
Component:	general	Assignee:	KWrite Developers <kwrite-bugs-null>
Status:	RESOLVED WORKSFORME
Severity:	major	CC:	christoph, waqar.17a
Priority:	NOR
Version First Reported In:	24.08.2
Target Milestone:	---
Platform:	Arch Linux
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description l33tmmx 2024-10-15 05:53:10 UTC

SUMMARY

So, Arch Linux got Qt-6.8.0 update this morning... I noticed quite fast that the update broke Kate (and KWrite) quite badly: the fonts on the editor are completely, repeat completely invisible. They are not black or white, or the editor theme-defined color; it seems that the font color is always exactly the same as the background color of the editor area, regardless of the chosen theme. I tried quite a lot of combinations of UI/editor themes, but no luck...

I haven't noticed any ill effects to other KDE applications so far.

STEPS TO REPRODUCE
1. Update to Qt-6.8.0
2. Start Kate
3. Try to write something...

OBSERVED RESULT

Invisible fonts

EXPECTED RESULT

Visible fonts

SOFTWARE/OS VERSIONS
Windows: 
macOS: 
(available in the Info Center app, or by running `kinfo` in a terminal window)
Linux/KDE Plasma: Arch Linux
KDE Plasma Version: 6.2.0
KDE Frameworks Version: 6.7.0
Qt Version: 6.8.0 

ADDITIONAL INFORMATION

Comment 1 l33tmmx 2024-10-15 06:02:42 UTC

May be caused by frameworks update to 6.7.0, too

Comment 2 Christoph Cullmann 2024-10-16 09:55:41 UTC

I have here KF 6.7 and Qt 6.8 and it works for me with both Wayland and X11.

Comment 3 l33tmmx 2024-10-16 16:44:43 UTC

Has this something to do with that I use Kate outside Plasma, that is, I'm not using KDE desktop, but Awesome WM.
And just noticed that Konsole has exactly the same problem :(

Comment 4 Waqar Ahmed 2024-10-16 18:36:48 UTC

You can try to enable logging, maybe that will help figure out whats going wrong. Maybe there is a bad font or something.

QT_LOGGING_RULES="*=true" kate -b -n .

Comment 5 Christoph Cullmann 2024-10-19 18:38:46 UTC

Yeah, please try that. For me Kate works fine with Qt 6.8 even outside of KDE Plasma.

Comment 6 Bug Janitor Service 2024-11-03 03:46:28 UTC

🐛🧹 ⚠️ 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 7 l33tmmx 2024-11-16 16:43:52 UTC

Sorry for a way too long delay in answering.

You were partially right: not a bad font but a bug in Qt-6.8.0 font handling: I was using (and had used it for years) Terminus font with anti-aliasing and hinting turned off for maximum sharpness; Qt-6.8.0 cannot handle that.

Comment 8 Bug Janitor Service 2024-12-01 03:46:14 UTC

🐛🧹 ⚠️ 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 9 Bug Janitor Service 2024-12-16 03:47:00 UTC

🐛🧹 This bug has been in NEEDSINFO status with no change for at least 30 days. Closing as RESOLVED WORKSFORME.