Nav Modifier volumes are not affected the nav mesh until they are moved from their initial placement position.
Found in 4.13.1. Reproduced in 4.12.5 and 4.15 Main CL 3163223
This is similar to UE-30174, but a different repro and with a different volume.
Result: Notice that the nav modifier does not affect the nav mesh until it is moved
Expected: The nav modifier volume would affecting the nav mesh immediately.
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