Oh, I see. Thanks for the quick response.
That icon and tooltip are very misleading (thank you for pointing this out). What it is trying to communicate is that, when you constrain two components, we temporarily ground the first so that the second moves to the first, instead of vice-versa. The components are not persistently grounded. You can actually go ahead and pick the second component at this point, and it all should work fine.
Sorry for the confusion.
Jeff Strater (Fusion development)
Jeff Strater
Engineering Director