@tony1tf, I'm sure you have checked this conversation about Mac Web IDE problems. So it is the OS X version that messes with you... (according to my post there, I had already moved on... and it is about the time when I started to do Espruino 7/2014).
I know that there are other ways to talk to (standard) Espruino (board) than USB... don't know about Pico.
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
@tony1tf, I'm sure you have checked this conversation about Mac Web IDE problems. So it is the OS X version that messes with you... (according to my post there, I had already moved on... and it is about the time when I started to do Espruino 7/2014).
I know that there are other ways to talk to (standard) Espruino (board) than USB... don't know about Pico.