The debugger should never have been included in ESP8266 builds, I'll see about taking it out. Due to the way it works it'll never be usable on ESP8266 I'm afraid. I'm unsure if it'd even work on ESP32.
If you need it you're best off using one of the proper Espruino boards
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.
The debugger should never have been included in ESP8266 builds, I'll see about taking it out. Due to the way it works it'll never be usable on ESP8266 I'm afraid. I'm unsure if it'd even work on ESP32.
If you need it you're best off using one of the proper Espruino boards