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- fix: restore directory on 'edit' load file.
- fix: undo button not disabled when no undo available
- feat: store undo/redo state, so it is available again when editing
- fix: no columns selectable on erroneous transformation line
- fix: first transformation line can not be deleted
- feat: auto quote filter values for string columns
- fix: selecting a different dataframe the second time in the transformation panel doesn't show the right dataframe
- feat: Add option to use markdown cells and dataframes in app builder