From emsdk version 3.1.0 (see https://emscripten.org/docs/introducing_emscripten/release_notes.html) ES6 is used in the core libraries, this means that we can try to use such feature in artoolkit.api.js or maybe, at least, create an alternative artoolkit_ES6.api.js for testing.
From emsdk version 3.1.0 (see https://emscripten.org/docs/introducing_emscripten/release_notes.html) ES6 is used in the core libraries, this means that we can try to use such feature in artoolkit.api.js or maybe, at least, create an alternative artoolkit_ES6.api.js for testing.