Lightroom Classic renders local Radial Gradient masks differently in Develop vs Library/Export

Lightroom Classic renders local Radial Gradient masks differently in Develop vs Library/Export

Hi,

I have a reproducible issue in Lightroom Classic that started after moving to a new computer.

My workflow relies on presets containing local Radial Gradient masks.

On certain photos (not all), the image looks correct in the Develop module, where the Radial Gradient is applied properly.

However, when I switch to the Library module, the image immediately becomes darker, as if the Radial Gradient mask is no longer being applied.

The exported JPEG matches the Library module, not the Develop module.

I have already tried:

* Updating Lightroom Classic to version 15.4.1
* Rebuilding previews
* Disabling GPU acceleration
* Creating new previews
* Testing on multiple images

Additional findings:

* The issue only happens on certain photos.
* It is related to local Radial Gradient masks.
* Creating a completely new Radial Gradient on a different image works correctly.
* Saving the problematic edit as a preset reproduces the issue on another image.
* The problematic images may contain only two Radial Gradient masks—nothing unusually complex.

I have attached a RAW file for exm. that reproduces the problem.

Is this a known bug, or is there anything else I can test?