Dragging parts in Layout view results in a flood of "Set an active layer" errors


I’m working on my first layout in Upverter and am just getting settled with the interface differences compared to Altium.
I’m trying to drag any component around and immediately am slammed with endless error notifications “Set an active layer (top or bottom copper) to see pins on that layer.”
Each time I nudge a footprint, I get more notifications.
Setting to a single active layer does not even appear to resolve this.
What is the problem here?


Update - I’ve reloaded the page and this no longer happens. Not sure what the original cause was…