In collaborations, the “thumbs up” button occupies the place where the Edit Mode button usually lives
Have User B create an element and add User A as a collaborator.
As User A, enter view mode on that element.
The Edit Mode button is no longer the leftmost button, instead, Thumbs Up is there.
This is a muscle memory issue, I find myself constantly clicking the thumbs up button by accident when attempting to return to edit mode on the collaborated scene because it is the leftmost button. Please always let Edit Mode be the leftmost item.