Hi Cool tool. One question: with Yaml being used to fill in the possible choice of a selection-box, how do I make the choices dynamic?

You can't dynamically set values in widgets. All values (choices and ranges) should be set upfront.

Ok, still could be useful, as indeed the one kernel per session design of alternatives like AppMode or VoilĂ  is a bit limiting. While you're here: how do I best display a pandas dataframe with Mercury?

The same was as you display in Jupyter. Just exectue the cell with your data frame variable.

The alternative might be to use rich package (https://github.com/Textualize/rich) but I don't have a tutorial yet.