A long standing Rhino 5 quirk

Ocassionally while working on a model, I somehow trigger either a glitch or some sort of command that I am unaware of that will cause this strange sheen to expand over 3 of the 4 viewports. When it happens it sort of greys out the entire linework of the model in Wireframe view. Switching that panel view to Shaded hides the issue, but it is still there if i switch back to Wireframe which is how I prefer to work in the ortho views.
Is this just a glitch or is Rhino trying to tell me something about my model?

Hi Drew - I would say that comes from the display mode settings for the grid, but I cannot reproduce it here.
Please take a screen shot of Options > OpenGL page and post it here.


Thanks for the quick reply, Pascal.
Unfortunately I have saved and closed out of the file, and now that it is reopened, the issue is gone. Although sometimes that issue is saved with the file, and remains when it is reopened.
But here is a screenshot of Options>OpenGL.

Hi Drew - I think I might do a clean install of the latest NVidis driver - no date or driver version shows for it there.