Bug 430439

Summary:	Going to 0% brightness using the applet's slider doesn't turn off the backlight; 0% using keyboard actions does
Product:	[Plasma] Powerdevil	Reporter:	postix <postix>
Component:	general	Assignee:	Plasma Bugs List <plasma-bugs>
Status:	RESOLVED FIXED
Severity:	normal	CC:	dmatteo002, eliadevito, glifwentry, natalie_clarius, nate, nikolai.bjerke.sakariassen2, now.im.627, postix, russianneuromancer, tinozzo123
Priority:	NOR
Version:	5.20.4
Target Milestone:	---
Platform:	Other
OS:	Other
Latest Commit:	https://invent.kde.org/plasma/powerdevil/-/commit/e1e74f37ea6ba4d3450ae79ede25a7cac1dd9a84	Version Fixed In:	6.0
Sentry Crash Report:

Description postix 2020-12-15 17:54:58 UTC

SUMMARY

There are to ways to change the brightness of the screen:
Fn + brightness keys or the energy plasmoid. 

For the first case it goes in steps of 5%:
100%, 95% ... 10% 5% OFF

The plasmoid's slider however is more fine graded and has a significant difference: 0% does not turn off the screen but dims it to the lowest level or to a level which is way below the 5%, which makes it very pleasant for the eyes in the night.

Turning off the screen is not possible here, though.

I'd like to propose to add an extra step for the "Fn + Brightness key" solution: 5% __0%__ OFF.



SOFTWARE/OS VERSIONS
Operating System: Manjaro Linux
KDE Plasma Version: 5.20.4
KDE Frameworks Version: 5.76.0
Qt Version: 5.15.2
Kernel Version: 5.9.11-3-MANJARO
OS Type: 64-bit
Processors: 4 × Intel® Core™ i7-7500U CPU @ 2.70GHz
Memory: 15.4 GiB of RAM
Graphics Processor: Mesa Intel® HD Graphics 620

Comment 1 Nowshed H. Imran 2020-12-16 15:17:08 UTC

I can confirm this. Display shouldn't just turn blank. It can be like this,
5% then 1% then blank.

Comment 2 Nate Graham 2020-12-16 21:21:57 UTC

It's true: setting the slider to 0% doesn't turn off the backlight the way going down to 0% using the keyboard actions does.

Comment 3 Martino Fontana 2022-06-19 22:34:58 UTC

Testing right now, the Fn keys and the plasmoid have the same behavior: neither of them can turn off the screen.

Comment 4 dmatteo002 2023-04-21 16:30:20 UTC

I've tested in Plasma 5.27.4 on Wayland and neither does seem to actually turn off the screen With the slider I got to 1% while dragging and 0% only with arrow key; instead with Fn + brightness keys I got to 0%; but in all the cases I could still see the content even if very faintly.
KDE Plasma 5.27.4
KDE frameworks Version: 5.105.0
Qt Version: 5.15.9
Kernel Version: 6.2.11-arch1-1 (64 bit)
Graphics Platform: Wayland

Comment 5 Natalie Clarius 2023-08-13 18:47:46 UTC

*** Bug 445529 has been marked as a duplicate of this bug. ***

Comment 6 Natalie Clarius 2023-08-13 18:51:47 UTC

Fixed with https://invent.kde.org/plasma/powerdevil/-/merge_requests/184; now the decrease key will no longer turn the screen off and instad  cap it at the same minimum brightness as the slider in the battery applet already does.

Comment 7 Nate Graham 2023-08-13 19:10:11 UTC

*** Bug 467910 has been marked as a duplicate of this bug. ***

Comment 8 Nate Graham 2023-08-21 17:50:17 UTC

*** Bug 403125 has been marked as a duplicate of this bug. ***

Comment 9 Jakob Petsovits 2024-07-18 07:22:45 UTC

Git commit 6ca6308ccd2f3266f20f84af6658fa97547e12ee by Jakob Petsovits.
Committed on 18/07/2024 at 07:13.
Pushed by jpetso into branch 'master'.

wayland: Use brightness range 1..max for internal displays

This avoids regressing compared to PowerDevil in 6.1 which also
protected against setting internal display brightness to 0.
Related: bug 483490

M  +2    -1    src/wayland/externalbrightness_v1.cpp

https://invent.kde.org/plasma/kwin/-/commit/6ca6308ccd2f3266f20f84af6658fa97547e12ee