FYI - Royal has added now added electrical outlet multiplier devices to the “banned” list.
As a long time (now retired) career electronics technician, I find this to be completely unnecessary, even stupid, safely overkill. The previous “banned” list already included any high current items that would overload a circuit.
So, now, you can’t charge two cell phones on the same outlet at the same time even though they are very low current devices.