Created attachment 136071 [details]
16b grey image

SUMMARY
I cannot change exposure (with either 'y'-leftbutton or via the "LUT Management" Docker) on HDR image since version 4.1.8.

STEPS TO REPRODUCE
1. Run any Krita after 4.1.8 and open a 16-bit grey image
2. Enable LUT Management
2. Hold down 'y', left-click, and drag up or down

OBSERVED RESULT
Image exposure does not change (on krita 4.3.0 rpm on Fedora 31, krita 4.4.2 appimage on Fedora 29, 31, or 33, or krita appimage 4.2.0, 4.2.8, 4.3.0 on Fedora 29).

EXPECTED RESULT
Image exposure does change (on Fedora 29, krita 4.1.8 rpm or manual compile, or krita 4.1.7 appimage)


SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Fedora 29, 31, 33
KDE Plasma Version: 
KDE Frameworks Version: 5.68.0
Qt Version: 5.13.2 (system)

ADDITIONAL INFORMATION

I'm honestly not sure if this is a bug in 4.1.8 and before and it *shouldn't* be working there, or a bug in krita 4.2.0 and since then, and it *should* be working.

I have OpenColorIO-1.1.1 installed, but strangely, in the LUT Management docker, "Color engine" is always set to "Internal" on both the working and non-working versions.

I double-checked the keyboard shortcuts to make sure that "Y + Left Button" is set to "Exposure Mode".

I even build krita 4.1.8 from scratch on Fedora 29 and it behaved the same as the rpm (it worked). Krita 4.1.7 AppImage also works as expected. Everything since 4.2.0 does not work.

I'd like to leave three attachments: screen shot of desired and nonfunctional behavior, and sample image that I am using. But since I get only one, it's a sample image.

Finally, I'm not sure if the Component should be "Color models" or "HDR" or "Shortcuts and Canvas Input Settings". It seems that the bug could be anywhere (or in my environment).