If I save a label preset with e.g. 10 labels once, it sometimes saves -1, which means that the last added label is not saved and therefore only 9 are displayed when the preset is reopened.

Version: release 2023.12, 64-bit Windows 10.

How to reproduce:

1. create a segmentation for an image
2. add 9 labels
3. Save the label preset under a file.
4. Delete the segmentation
5. Create a new segmentation
6. Reload the label preset from a file
7. Then the last label is missing.