Visual Editor Bug

Hi,
I’m using Luminescence Lite, Version: 2.2.0, which I downloaded fresh this evening from the wordpress site.
When using the visual editor, instead of the editor looking like it normally does – e.g.
https://i.imgur.com/RAXzcch.png
The editor changes to this when using this theme:
https://i.imgur.com/2EpklEQ.png

There is no padding around the text, and the text is all in grey. If I apply formatting to the text, e.g. bullet points, those cannot be seen because of the way the text is formatted in the editor.

I have tried:

1. Deleting browser cache
2. Disabling add-ons
3. Reinstalling the theme
4. I have tried in Firefox and Chrome. I’m using Windows 10

Is there any way around this issue?

Thanks