Description:
The Navigation Bar flashes, when using the command "Content Navigation Bar".
(You can find the button on top left of the Navigation Bar.)
This really irritates me... :-(

This Bug only occurs, when OpenGL Rendering is disabled. When OpenGL is enabled, there is no flashing.
(If You now asking 'Why just dont enable OpenGL??' -> I dont like OpenGL Rendering on LibO. First, the UI lags with OpenGL, especially the dropdown menus. Second, many fonts looks really horrible with OpenGL. I dont know why, but that's the way things are.)

This bug occurs after updating LibO from 6.2 to 6.3

Steps to Reproduce:
1. Tools -> Options -> View -> Disable OpenGL Rendering
2. Open a Text Document with headings (the headings has to be defined by style sheet "Heading", so that they are shown in Navigation Bar)
3. (in Navigation Bar) Click on a heading -> Content Navigation Bar


Actual Results:
Navigation Bar flashes

Expected Results:
It should not flash


Reproducible: Always


User Profile Reset: No



Additional Info:
Version: 6.3.3.2 (x64)
Build ID: a64200df03143b798afd1ec74a12ab50359878ed
CPU threads: 2; OS: Windows 10.0; UI render: default; VCL: win; 
Locale: de-DE (de_DE); UI-Language: en-GB
Calc: threaded