Description:
After updating to 6.3.3 from 6.2.4, a timed refresh redraw of the Navigator panel is happening, apparently at about a 1 per second interval. This is extremely distracting visually.

I use the Navigator for Headings navigation, and had the Navigator panel docked to the left side of the app frame. However

The workaround for me is to   

Steps to Reproduce:
1. Open a .odt with a number of H1-H3 chapter headings (don't think the content is part of the issue)
2. Display the Navigator, enable Content Navigation View. I have Heading Levels  Shown set to 3 (but don't think that directly relates to the refresh polling issue)


Actual Results:
Whether docked or floating, I'm seeing a full refresh of the Headings content approx once per second. Updating for heading changes in the document is of course expected, but not the flicker/visible refreshing. NOTE you may have to set focus into the document to start this happening.

Expected Results:
No refresh redraw flickering


Reproducible: Always


User Profile Reset: No


OpenGL enabled: Yes

Additional Info:
KEY TESTING OBSERVATION: If I turn OFF Content Navigation View (one of the panel's own toolbar buttons), I'm no longer able to reproduce this problem. So the workaround if wanting to keep the Navigator panel visible for extended periods of time is to do that. Alternatively, just use it as a "pop up" via F5, use, and close.