Yes, a bit of follow up here. The comments about using a UK adapter are centered around making sure the plug fits securely in the socket. I imagine (but can not confirm) a two rounded prong Euro or Latin American plug would also work better than the plain U.S. plug on the aircraft.

A completely separate issue is the size of the charging brick. While some folks say a 99 watt brick will work, my understanding is the outlets are rated at 75 watts max. So if I were shopping for a new charger, I would get one at 75 watts or less. There are plenty to choose from, especially if your laptop uses a USB C connection. Even if the laptop draws 100 watts, that is typically at peak power with peak demand. A 65 watt charger will certainly charge when the laptop is closed and at rest, and will slowly charge (or slow the rate of discharge) depending on the power draw when the laptop is being used.