• My guess is the IDE is set to automatically minify modules, so when you include via the IDE they get minified.

    Espruino doesn't handle let with scoping, so it's possible if you have used let in your code a lot the minifier has decided to name two variables a in the same function, and that's causing some issues? Maybe if you disable module minification in the IDE settings it'll work which will at least prove the problem?

  • Yes, that's it!

    Both problems disappear as soon as I disable module minification.

    May I solve this problem by using var instead of let?