until recently the Night Light utility in the tray used to be adjustable by 1% steps when the Shift key was used, however this no longer works; holding Shift prevents any change and the step size without Shift is 5%
Fn+Shift+F1/F2 still adjusts in 1% steps
KDE Plasma Version: 6.1.5
KDE Frameworks Version: 6.6.0
Qt Version: 6.7.2
Kernel Version: 6.10.13-3-MANJARO (64-bit)
Graphics Platform: X11
Could you tell us which “night light utility” please? I assume you don’t mean the usual screen brightness adjustments via scrolling whilst hovering over the icon?
… This is still in 1% steps for me; tried your method using SHIFT in conjunction with the Fn and, on my machine, F5 and F6 keys.
I’m using the linux66 LTS series at present.
Does switching to a Plasma Wayland session make any difference?
I just tried adjusting the brightness on my Plasma Wayland session by holding the shift key while scrolling the mouse wheel over the brightness icon in the system tray, and it did it in 1% increments. I also learnt that it works the same way with the volume icon - 5% without the shift key, 1% with the shift key.
Although it should be noted that I am on Testing branch, which means I am on Plasma 6.2.2, while Stable branch is on Plasma 6.1.5.
Good point there @scotty65. I forgot to mention I’m also using Wayland. 
I’ve set my volume to always use 1% steps; at least this one is easily changed in System Settings.
yes, i meant the sys tray util that’s packaged with plasma - it no longer adjusts brightness in 1% steps with shift key
haven’t tried wayland, and yes, shift works in 1% steps for me with the volume icon
I’d certainly give Wayland a go, nothing to lose as it’s easily switchable via the SDDM login screen (bottom left, usually).
Another thing worth trying is the linux66 kernel, and/or linux611 to see if it might be driver (integration?) related (which I sort of doubt in this case but no harm in giving them a go).
A bit more detail on your system may also be helpful:
inxi -zv8
.
issue was the same on wayland and the 6.6 kernel - i’ll give the 6.11 kernel a shot tomorrow
inxi is spitting out a lot of info that i’d have to go though before posting
If privacy is an issue, rest assured, the following inxi command filters out all personally identifiable information;
inxi --admin --verbosity=8 --filter --no-host --width
Cheers.
thanks for the inxi syntax - i’ll go with -v 5 for now if that’s ok 
$ inxi --admin --verbosity=5 --filter --no-host --width
System:
Kernel: 6.10.13-3-MANJARO arch: x86_64 bits: 64 compiler: gcc v: 14.2.1
clocksource: tsc avail: hpet,acpi_pm
parameters: BOOT_IMAGE=/boot/vmlinuz-6.10-x86_64
root=UUID=bb1d3d93-e1ee-4b58-94bc-d9b9b6f183a1 rw
resume=UUID=365557ba-d129-4798-90eb-91ecda0db65d udev.log_priority=3
nowatchdog
Desktop: KDE Plasma v: 6.1.5 tk: Qt v: N/A info: frameworks v: 6.6.0
wm: kwin_x11 vt: 2 dm: SDDM Distro: Manjaro base: Arch Linux
Machine:
Type: Desktop Mobo: Micro-Star model: B450 TOMAHAWK MAX (MS-7C02) v: 1.0
serial: <superuser required> uuid: <superuser required> UEFI: American
Megatrends LLC. v: 3.B0 date: 05/12/2021
Memory:
System RAM: total: 16 GiB available: 13.57 GiB used: 2.32 GiB (17.1%)
Message: For most reliable report, use superuser + dmidecode.
Array-1: capacity: 128 GiB slots: 4 modules: 2 EC: None
max-module-size: 32 GiB note: est.
Device-1: Channel-A DIMM 0 type: no module installed
Device-2: Channel-A DIMM 1 type: DDR4 detail: synchronous unbuffered
(unregistered) size: 8 GiB speed: 3200 MT/s volts: note: check curr: 1
min: 1 max: 1 width (bits): data: 64 total: 64 manufacturer: G.Skill
part-no: F4-3200C16-8GVGB serial: N/A
Device-3: Channel-B DIMM 0 type: no module installed
Device-4: Channel-B DIMM 1 type: DDR4 detail: synchronous unbuffered
(unregistered) size: 8 GiB speed: 3200 MT/s volts: note: check curr: 1
min: 1 max: 1 width (bits): data: 64 total: 64 manufacturer: G.Skill
part-no: F4-3200C16-8GVGB serial: N/A
CPU:
Info: model: AMD Ryzen 5 3400G with Radeon Vega Graphics bits: 64
type: MT MCP arch: Zen/Zen+ note: check gen: 1 level: v3 note: check
built: 2019 process: GF 12nm family: 0x17 (23) model-id: 0x18 (24)
stepping: 1 microcode: 0x8108109
Topology: cpus: 1x dies: 1 clusters: 1 cores: 4 threads: 8 tpc: 2
smt: enabled cache: L1: 384 KiB desc: d-4x32 KiB; i-4x64 KiB L2: 2 MiB
desc: 4x512 KiB L3: 4 MiB desc: 1x4 MiB
Speed (MHz): avg: 2300 min/max: 1400/3700 boost: enabled scaling:
driver: acpi-cpufreq governor: schedutil cores: 1: 2300 2: 2300 3: 2300
4: 2300 5: 2300 6: 2300 7: 2300 8: 2300 bogomips: 59229
Flags: avx avx2 ht lm nx pae sse sse2 sse3 sse4_1 sse4_2 sse4a ssse3 svm
Vulnerabilities:
Type: gather_data_sampling status: Not affected
Type: itlb_multihit status: Not affected
Type: l1tf status: Not affected
Type: mds status: Not affected
Type: meltdown status: Not affected
Type: mmio_stale_data status: Not affected
Type: reg_file_data_sampling status: Not affected
Type: retbleed mitigation: untrained return thunk; SMT vulnerable
Type: spec_rstack_overflow mitigation: Safe RET
Type: spec_store_bypass mitigation: Speculative Store Bypass disabled via
prctl
Type: spectre_v1 mitigation: usercopy/swapgs barriers and __user pointer
sanitization
Type: spectre_v2 mitigation: Retpolines; IBPB: conditional; STIBP:
disabled; RSB filling; PBRSB-eIBRS: Not affected; BHI: Not affected
Type: srbds status: Not affected
Type: tsx_async_abort status: Not affected
Graphics:
Device-1: Advanced Micro Devices [AMD/ATI] Picasso/Raven 2 [Radeon Vega
Series / Radeon Mobile Series] driver: amdgpu v: kernel arch: GCN-5
code: Vega process: GF 14nm built: 2017-20 pcie: gen: 3 speed: 8 GT/s
lanes: 16 ports: active: HDMI-A-1 empty: DVI-D-1,HDMI-A-2,HDMI-A-3
bus-ID: 27:00.0 chip-ID: 1002:15d8 class-ID: 0300 temp: 42.0 C
Display: x11 server: X.Org v: 21.1.14 with: Xwayland v: 24.1.4
compositor: kwin_x11 driver: X: loaded: modesetting alternate: fbdev,vesa
dri: radeonsi gpu: amdgpu display-ID: :0 screens: 1
Screen-1: 0 s-res: 1920x1080 s-dpi: 96 s-size: 508x285mm (20.00x11.22")
s-diag: 582mm (22.93") monitors: <missing: xrandr>
Monitor-1: HDMI-A-1 model: BenQ EX2510 serial: <filter> built: 2020
res: 1920x1080 dpi: 90 gamma: 1.2 size: 544x303mm (21.42x11.93")
diag: 623mm (24.5") ratio: 16:9 modes: max: 1920x1080 min: 720x400
API: EGL v: 1.5 hw: drv: amd radeonsi platforms: device: 0 drv: radeonsi
device: 1 drv: swrast gbm: drv: kms_swrast surfaceless: drv: radeonsi x11:
drv: radeonsi inactive: wayland
API: OpenGL v: 4.6 compat-v: 4.5 vendor: amd mesa v: 24.2.4-arch1.0.1
glx-v: 1.4 direct-render: yes renderer: AMD Radeon Vega 11 Graphics
(radeonsi raven LLVM 18.1.8 DRM 3.57 6.10.13-3-MANJARO)
device-ID: 1002:15d8 memory: 1.95 GiB unified: no
API: Vulkan v: 1.3.295 layers: N/A device: 0 type: integrated-gpu name: AMD
Radeon Vega 11 Graphics (RADV RAVEN) driver: mesa radv v: 24.2.4-arch1.0.1
device-ID: 1002:15d8 surfaces: xcb,xlib
Audio:
Device-1: Advanced Micro Devices [AMD/ATI] Raven/Raven2/Fenghuang HDMI/DP
Audio vendor: Micro-Star MSI driver: snd_hda_intel v: kernel pcie: gen: 3
speed: 8 GT/s lanes: 16 bus-ID: 27:00.1 chip-ID: 1002:15de class-ID: 0403
Device-2: Mark of the Unicorn M Series driver: cdc_acm,snd-usb-audio
type: USB rev: 2.0 speed: 480 Mb/s lanes: 1 mode: 2.0 bus-ID: 1-1:2
chip-ID: 07fd:000b class-ID: 0a00 serial: <filter>
API: ALSA v: k6.10.13-3-MANJARO status: kernel-api with: aoss
type: oss-emulator tools: alsactl,alsamixer,amixer
Server-1: JACK v: 1.9.22 status: off tools: N/A
Server-2: PipeWire v: 1.2.5 status: active with: 1: pipewire-pulse
status: active 2: wireplumber status: active 3: pipewire-alsa type: plugin
tools: pactl,pw-cat,pw-cli,wpctl
Network:
Device-1: Realtek RTL8111/8168/8211/8411 PCI Express Gigabit Ethernet
vendor: Micro-Star MSI driver: r8169 v: kernel pcie: gen: 1 speed: 2.5 GT/s
lanes: 1 port: f000 bus-ID: 22:00.0 chip-ID: 10ec:8168 class-ID: 0200
IF: enp34s0 state: up speed: 1000 Mbps duplex: full mac: <filter>
IF-ID-1: azirevpn-us-mia state: unknown speed: N/A duplex: N/A mac: N/A
Info: services: NetworkManager,systemd-timesyncd
Drives:
Local Storage: total: 9.1 TiB used: 2.3 TiB (25.2%)
SMART Message: Unable to run smartctl. Root privileges required.
ID-1: /dev/nvme0n1 maj-min: 259:0 vendor: Western Digital
model: WDS100T3XHC-00SJG0 size: 931.51 GiB block-size: physical: 512 B
logical: 512 B speed: 31.6 Gb/s lanes: 4 tech: SSD serial: <filter>
fw-rev: 102000WD temp: 44.9 C scheme: GPT
ID-2: /dev/sda maj-min: 8:0 vendor: Samsung model: SSD 860 EVO 1TB
size: 931.51 GiB block-size: physical: 512 B logical: 512 B speed: 6.0 Gb/s
tech: SSD serial: <filter> fw-rev: 4B6Q scheme: GPT
ID-3: /dev/sdb maj-min: 8:16 vendor: Crucial model: CT2000MX500SSD1
size: 1.82 TiB block-size: physical: 4096 B logical: 512 B speed: 6.0 Gb/s
tech: SSD serial: <filter> fw-rev: 033 scheme: GPT
ID-4: /dev/sdc maj-min: 8:32 vendor: Samsung model: SSD 870 EVO 4TB
size: 3.64 TiB block-size: physical: 512 B logical: 512 B speed: 6.0 Gb/s
tech: SSD serial: <filter> fw-rev: 3B6Q scheme: GPT
ID-5: /dev/sdd maj-min: 8:48 vendor: SanDisk model: SDSSDH32000G
size: 1.82 TiB block-size: physical: 512 B logical: 512 B speed: 6.0 Gb/s
tech: SSD serial: <filter> fw-rev: 70RL scheme: MBR
Message: No optical or floppy data found.
Partition:
ID-1: / raw-size: 905.34 GiB size: 890.05 GiB (98.31%) used: 15.2 GiB (1.7%)
fs: ext4 dev: /dev/nvme0n1p3 maj-min: 259:3 label: Root
uuid: bb1d3d93-e1ee-4b58-94bc-d9b9b6f183a1
ID-2: /boot/efi raw-size: 300 MiB size: 299.4 MiB (99.80%)
used: 296 KiB (0.1%) fs: vfat dev: /dev/nvme0n1p1 maj-min: 259:1 label: BOOT
uuid: 61A2-791F
ID-3: /home raw-size: 931.02 GiB size: 915.33 GiB (98.31%)
used: 99.45 GiB (10.9%) fs: ext4 dev: /dev/sda1 maj-min: 8:1 label: Home
uuid: d186724a-14d9-46e5-a29d-b16ae175fd25
Swap:
Kernel: swappiness: 20 (default 60) cache-pressure: 100 (default) zswap: yes
compressor: zstd max-pool: 20%
ID-1: swap-1 type: partition size: 25.39 GiB used: 0 KiB (0.0%)
priority: -2 dev: /dev/nvme0n1p2 maj-min: 259:2 label: swap
uuid: 365557ba-d129-4798-90eb-91ecda0db65d
Sensors:
System Temperatures: cpu: 41.6 C mobo: N/A gpu: amdgpu temp: 41.0 C
Fan Speeds (rpm): N/A
Info:
Processes: 272 Power: uptime: 22m states: freeze,mem,disk suspend: deep
avail: s2idle wakeups: 0 hibernate: platform avail: shutdown, reboot,
suspend, test_resume image: 5.41 GiB services: org_kde_powerdevil,
power-profiles-daemon, upowerd Init: systemd v: 256 default: graphical
tool: systemctl
Packages: pm: pacman pkgs: 1426 libs: 308 tools: pamac Compilers:
gcc: 14.2.1 Shell: Bash v: 5.2.37 running-in: konsole inxi: 3.3.36
This is definitely worth knowing.
I wasn’t aware you could adjust brightness settings on an external monitor without using xrandr settings (which I used on a be-headed laptop with external monitor(s), to set brightness and contrast levels for night use, but have since forgotten how, unfortunately). Naturally, this had no effect on the monitor backlight, being an LCD.
Kernel 6.10 has reached EOL.
General availability of kernel 6.12 (LTS) is expected this month.
Though these have no obvious bearing on your issue.
I use Wayland; the step size seems to be as expected. It has been a year since using X11 (except on Debian and BSD) so I can’t comment much on that.
Good luck.
the issue is the same with wayland
Perhaps kernel 6.12 (LTS) will weave some magic.
Create a new User account, and see if you have the same issue there. This will usually indicate whether the issue is limited to your current User; or rule it out.
Otherwise 
One other thing that I would like you to do is check the change brightness by 1% shortcuts on your system. They can be accessed via:
System Settings => Keyboard => Shortcuts => Power Management
The shortcut for “Decrease Screen Brightness by 1%” should be “Shift+Monitor Brightness Down”
The shortcut for “Increase Screen Brightness by 1%” should be “Shift+Monitor Brightness Up”
@scotty65 - the shortcuts are correct and match what you specified
i re-read all the replies here (and thanks everyone for jumping in to help) and it isn’t clear to me whether anyone has tested the sys tray night light brightness thingy to see if it works in 1% increments on X11 (Shift key + mouse wheel)
next i guess i’ll test under a fresh user acct. because i’m suspecting the issue may be a config file in /home, but if anyone knows which file that may be, please let me know