The awesome YouTube channel GreatScott!
just posted a new project. He now made a new PCB that could control the paower of AC voltage. So, please, if you want to try this same circuit, be careful working with high AC voltage because this could be lethal. That been said, let's see this new PCB. First of all, he explain us how we could control AC voltage using TRIACs with a DIAC circuit that will apply a small pulse at the TRIAC gate each zero-cross of the AC signal. We could add a potentiometer to this circuit and it would work just fine for normal incandescent AC light bulbs. But he also wants to control the power for LED high voltage lights and with this simple circuit that won't work.
So, a more digital and precise control is needed and is that why he designed a new PCB and compare it with a commercial product that dose the same.