Can't delete the Login Widget in Upfront after editing Default Appearance

Trying to set up a buddypress login using Upfront (Fixer Theme). Dragged in the 'Login' Widget and started customizing (--> Appearance --> Edit Default Preset). Now it doesn't allow me to delete it.
Can't click the red x button: when hovering over, the cursor doesn't change into the clicky finger like it does on the other widgets.

Tried deleting cache, too - problem persists.

If I do not customize the widget, deleting is possible.

I am by now giving shelter to five tenacious login buttons. Please help me send them off my premises.