How do I set "data-xxx" attributes on widgets?

[TreyBoudreau]

I'd like to set a data attribute on widgets, as per https://developer.mozilla.org/en-US/docs/Learn/HTML/Howto/Use_data_attributes

I've tried using create_element('div', {'data-my-prop': 'my value'}, ...) but something in Flexx seems to strip them out.

Any clues?

[almarklein]

I wonder whether the way the attribute is set works:

flexx/flexx/ui/_widget.py

Line 502 in 69b85b3

ob[map.get(key, key)] = val

Could be that node.setAttribute is needed.