I am a pretty much unexperienced (x)ubuntu user, so I am sorry if my question has a pretty obvious answer I failed to find.
The problem I am having are some incorrectly displayed fonts in the UI-windows of Writer, Calc, Base, Impress and Draw (see image below ).
In Writer, Base and Calc, some of the bold text in the windows appears as a collection of scattered black boxes, rectangles. The text is completely unreadable. In Impress and Draw, the glitches are of white colour and the text is readable, but only with difficulty.
I have tried removing and reinstalling LO, but to no avail. Switching on and off anti-aliasing has also rendered no result.
I am using LibreOffice v. 22.214.171.124. My OS is Xubuntu 16.04 (x64) as a dual boot alongside Win7 on a Lenovo Thinkpad e555, equipped with a Radeon R6 Graphics card. No proprietary drivers are in use.
I will gladly provide any further information or any command-outputs you require.
Thank you for your help in advance!