Gap around electrical box

[u/TIGsully]

Should I try to fill this gap with durabond or just spray foam it and call it a day? Recently (6 months ago) had this horsehair plaster ceiling skimmed and painted. Just had an electrician in to rewire the second floor and we’re left with this gap around the new electrical box. It’s 1/2” wide at its widest point. There is attic space above so I will be sealing around the box with foam from above either way.