I want to open 3mf files not as “geometry only” but I can’t find were to change that setting it popped up once and I can’t find it anywhere any more.
Do you want to import or open the 3mf? Those are different things but you are using them interchangeably.
I’ve only seen this message after opening a new file without closing out the first one. If you clear the plate before you open a new file, you should not see this message.
Whatever the “add” block does.