ID 420526 - Performance drop in OpenGL after modifying components of a displaced mesh

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Problem summary
Performance drop in OpenGL after modifying components of a displaced mesh. The mesh must be in catmull-clark or Subdivison mode.

Customer reported version
modo.13.2v1

Customer reported platform
windows10

Steps to reproduce
1) Open Modo.
2) Select File > open and open the attached scene. Located the imported images if necessary.
3) Press "1" to enter component selection mode.
4) Select a vertex on the mesh.
5) Press "W" to enable the move tool.
6) Move the vertex slightly. Modo should slow down.
7) Press "Q" to drop the tool.
Result: Modo should still be slow. Manipulating the viewport (i.e. rotating, zooming, panning) will be extremely sluggish.

Expected behaviour
Modo should not slow down after manipulating a component of a displaced mesh.

Actual behaviour
Modo slows down semi-permanently after manipulating a component of a displaced mesh in subdivision or catmull-clark mode.

Workaround
Switching the mesh to face mode and back should "reset" the performance drop, however it will re-occur if the mesh is manipulated.

Reproduced by support
This bug has been reproduced in:
13.2v1 - Windows 10, OSX 10.14.6
13.1v1 - Windows 10, OSX 10.14.6

Unable to reproduce bug in:
13.0v1 - Windows 10, OSX 10.14.6

Earliest version tested
13.0v1 - Windows 10, OSX 10.14.6 - This issue doesn't appear in this version and has regressed

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