datagrid table - no text input possible in HTML5

[UKMC]

I built a demostack with a datagrid which is editable - on windows, everything works perfect.

When making a HTML5 standalone App, there is no possibility to edit the contents.
Its clear to me that changes cannot be saved into the stack (as it is a standalone), but as I read on other places, editing should be possible (for example to store them in a database)
Sercond point is, that after building the html5-standalone, the grid is no löonger editable in LC itself.

I hope there is someone out there who can give me a hint.

Best regards

Ulrich