Add roots to curdoc() dynamically not updating

[Bryan]

@Cosmidark c.f. similar recent post

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@Omi The code does not work for me, so I guess I would regard it as a bug (please file a GitHub Issue with details). However I would also say completely clearing curdoc is uncommon usage. I’d suggest instead adding some top level layout container (e.g. row or column) once up front, and then replacing the contents inside the container, and see if that works better.

replace “completely clearing curdoc” with “adding roots dynamically” above.