XnView Software

XnViewMP 1.4.3 64bit
Windows11 (22H2), display resolution 3840x2160, win scaling 150%

Viewer
Image has dirty state (*) once instrument dialog is closed

To reproduce:
1. run clean portable XnViewMP
2. open any image

Issue A
3. open instrument*
make sure 'Apply to image' checkbox is unticked
4. close instrument
image will have dirty state (*)

* affected instruments:

• Image
  • Map
    - White Balance...
    - Solarize...
    - Posterize...
    - Sepia...
    - Vigneting...
    - Old camera...
  • Adjust
    - Levels...
    - Curves...
    - Shadow/Highlight...
    - Conbright/Gammasat...
  • Offset...

• Effect
  • Effect...
  • Film simulation...

Issue B
3. open 'Adobe Photoshop Plugin...' dialog in Effect menu
it has no plugins by defult
4. press OK
image will have dirty state (*)

Confirmed!

Also, "Save changed file" notification is invoked when closing image tab

Thanks to your detailed description I can reproduce the problem.

This problem is supposed to be fixed in XnView MP 1.5.0 beta. Please check and confirm the bug fix here.

fixed in 1.5.0