(1) Chromium does not have a Math.tanh(x) function!!!
    (in the net people say that ony Math.tanh(1000) etc undefined)
    => I wrote one locally myself in models.js

(2) Chromium does not allow local html inclusion in default state:
start with an option, e.g. for loading index.html:

chromium-browser --allow-file-access-from-files index.html