ID 486878 - Deleting unused Patch data can cause textures to become disordered

Problem summary
Deleting unused Patch data can cause textures to become disordered

Customer reported version
Mari 4.7v4

Customer reported platform
n/a

Steps to reproduce

1) Create two variations of a multi-UDIM mesh, or use the attached .obj files

Mesh B should have its UV shells moved so that there is an empty Patch:

Mesh A:

Mesh B:
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2) Create a new Project with Mesh A

3) Add Mesh B as a New Object Version and remove the original Object Version (Mesh A)

4) Create a Paint Node and paint a test texture

5) Save and Close the Project

6) Open Preferences and ensure that 'Delete Patch Data no Longer Required' checkbox is ticked (Data > Project)

7) Open the Project

Expected behaviour
The texture should look the same as it was when the project was saved.

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Actual behaviour
The textures appear on incorrect Patches, looking 'scrambled'.

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Workaround
Untick the 'Delete Patch Data no Longer Required' checkbox before loading the Project.

Reproduced by support
This bug has been reproduced in:
Mari 4.7v4 - Windows 10 - CentOS 7.7
Mari 4.7v3 - Windows 10 - CentOS 7.7

Earliest version tested
Mari 4.7v3 - This feature did not exist before this version