The Embedded component is there, but when I try to drag a Label component on it, it says “Could not drop that item there.”
How would I stack those two components? Do I need to use another layout than GridLayout? If so, how can I retain the 2x4 grid without using GridLayout?
You can simply add VBox to your GridLayout and then add Embedded and Label to this VBox.
GridLayout does not support multiple components in a cell so you have to use one of container components: VBoxLayout/HBoxLayout/GridLayout/etc.