I use an Ubuntu 16.04 VM with VirtualBox 5.1.14 on a Windows 10 host. I updated to the latest guest additions as well.
When I run Eclipse (Neon.2, 4.6.2) in the VM, my method hover dialog and Javadoc pane look like this:
I can use the same font (Ubuntu system) in other windows without problem and can change the background color. But clearly there's a problem in the text rendering.
If I force Eclipse to use GTK 2, my hover dialogs are fixed, but the Javadoc view has the message:
NOTE: The SWT Browser widget could not be created. This fallback mode doesn't show links and misses other functionality.
Any suggestions on how to get GTK 3 working again?