ID 376774 - Corrupt UVs when 'Thicken Polygons' is enabled for a polygon bevel mesh op

Problem summary

Enabling the 'Thicken Polygons' option on a polygon bevel mesh op displays corrupt UVs in the UV tab. Previewing the UVs for the mesh and not the polygon bevel mesh op, displays the expected UVs without any corruptions. 

Customer reported version
modo.12.1v1

Customer reported platform
windows7

Steps to reproduce
1) Open Modo.
2) Load the provided scene uvs_procedural_01b.lxo. This contains a polygon bevel mesh op with the 
3) Select the mesh and switch to the UV tab. Change the map to "texture" if it is not already selected.
Result: The UVs should appear correctly.
4) Select the polygon bevel and view the UVs.
Result: The UVs should be corrupted and look something like:

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Workaround
Disable the 'Thicken Polygons' option for the polygon bevel mesh op and the UVs display as expected. 

Reproduced by support

This bug has been reproduced in:

12.2v1 - Windows 10
12.0v1 - Windows 10
11.2v1 - Windows 10

Earliest version tested
11.2v1 - This feature (Thicken Polygons) did not exist before this version

Expected behaviour
The UVs should look correctly like for the main geometry when using polygon bevel mesh ops with the 'Thicken Polygons' options on or off

Actual behaviour
The UVs become corrupted when the 'Thicken Polygons' option for polygon bevel mesh ops is on.