Navmesh doesn't generate on Geometry Brushes on editor startup

Hi all,

I’m having an egregious problem where everytime I start the editor, the navmesh does not build on Geometry brushes. The only way to fix it is to move a brush slightly to get the navmesh to see the brushes.


And that’s good that it works again, but it happens EVERYTIME I launch the editor (which means I have to rebuild everything including lighting). Anyone know what might be causing this? This issue only propped up after migrating from 5.3 to 5.5 which I did a couple days ago.