Right Panel doesn't show properly. Ubuntu 17.08/18.04

Hi,

I’m having this problem since Ubuntu 17.08 and the latest version of LibreOffice. When I open Writer the right panel doesn’t show properly. This not happens for example with Calc. Only after refreshing the application, after opening a new document or doing minimize/maximize the panel appears correctly.

I have an nVidia GPU.

I Attached a screenshot.

Thank you.

(Edit: activated screenshot -AK)