Hello!
I opened the editor yesterday and wasn’t able to see the tracing preview of any glyph whenever I hit /Space bar, the preview does show up in the preview below, just not in the actual glyph
can you try to start Glyphs with the Option and Shift to disable plugins?
I tried this, but its still not showing anything 
How does it look when you do not press space?
Did you change the color setting (in the Appearance setting of Glyphs)? Try clicking the Standard button there and see if that fixes it.
Or do you have defined any Master colors?
This worked! Thank you!
So it was probably a bug right :S?
I hadn’t 