Why cant I see curves when moving/scaling/rotating in Rhino 6?

I’m unable to see my curves when moving/scaling/rotating etc. I can see a dotted outline if moving only one curve, but if I have multiple curves they all disappear while I’m moving them. They used to be visible in Rhino 5. If I start a drawing from scratch then I can see them but if I have to work on other peoples drawings then I usually cant. This must be a setting they introduced in Rhino 6 but I cant for the life of me find out how to change it, can anyone help at all? Thanks!

Hello - please run the SystemInfo command in Rhino and copy/paste the results here.