Usually it happens if it's not able to communicate with the board, so it can't tell which board it's talking to and so which libraries it already implements.
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.
Are you still connected with the main Web IDE?
Usually it happens if it's not able to communicate with the board, so it can't tell which board it's talking to and so which libraries it already implements.