Image variants are mixed across image sets

Reproduction steps:
1. Open the gallery manager.
2. Create 2 image set.
3. Add one new image variant to the first set with resolutions.
4. Save changes.
5. Reopen the gallery manager.
6. Select the 2nd image set.
7. Add a new image variant with the same name as the previous
8. Notice it loads the data from the previous saved state.
9. Change the resolution.
10. Save changes.
11. Check the image variant inside the first set.

Expected result:
They are not affecting each other.

Actual result:
The second change has overwritten the first variant properties.