I have built the bootloaders from this repo, with source code current as of now. Have been using make of Cygwin and also tried using Atmel/Microchip Studio. I guess there is no differencem since both ...

##### mega.name=Arduino Mega or Mega 2560 mega.vid.0=0x2341 mega.pid.0=0x0010 mega.vid.1=0x2341 mega.pid.1=0x0042 mega.vid.2=0x2A03 mega.pid.2=0x0010 mega.vid.3 ...