Online Firmware Builder

Thanks for feedback,
Not sure, I understand your question but let me try to give an answer

• take a look to Add extensions from Github and Add extensions from your computer, hope this is helpful to add your custom coding
  
• JsCommands is used to list all commands that are available in your firmware. This includes extensions added from github or from your local computer. Another function supported by JsCommands is to blacklist JS-commands that you don't want to have in your firmware.
  
• there is no dictionary for custom coded extensions. To be honest I couldn't find any in github or somewhere else.
  BTW, I use this tool to test and implement some extensions, which are tailor made for my needs (and interest).
  Right now I'm working on a stable process to get actual Espruino Source from github (https://github.com/espruino/Espruino) once a day