ESP32 not working if using external supply

Actually when we are powering the dev boards via the Vin and Gnd, we will have to add few resistors to for particular pins to boot.

I had faced the same problem with NODEMCU12E.
When powered via USB all works fine. When connected via Vin pin, the board doesn’t want to boot. I then connected pull down and pull up resistors to get the board working.