This release makes the loader's output red, so that it's easier to visually differentiate from the output of the loaded firmware.
It also makes button 0 on the A7 discard UART input. This is useful if you start loading the wrong thing: the loader will try to process it and will periodically jump into some nonsense code if it receives something that looks like a valid hex file. Holding button 0 will ignore the UART input until you release the button, at which point you can try loading again.