Non-Breaking characters such as en dash, em dash, en space,etc are highlighted in green in QuarkXPress 2017 so that users can easily recognize the inserted non-breaking characters.
Applies to - Win and Mac
Affects - QuarkXPress 2017
How to disable this feature:
1. Launch QuarkXPress 2017
2. Go to view and deselect the option "Highlight Non-Breaking Text"