I have a strange font problem where the numbers are missing until I highlight them on the page - see the screenshot below
It seems the numbers are showing up in white text on white background - but numbers only...

It only happens with some fonts and one some web pages with both Firefox and Chromium in the same way.

It looks like it's also happening in the console window - see the white numbers in the screenshot.

This started after a failed update to 15.0 which I managed to recover from with the help of the forum.
I did a 15.0 to 15.1 online upgrade hoping that might fix it but it hasn't.

- I've never changed any of the fonts from default settings anywhere.
The fonts problem happens in KDE and LXDE
Has anyone ever seen anything like this before?