JSON formatting: add support RTF multiline text fields
JSON formatting supports a few field types, but currently we cannot do any kind of JSON treatment on multiline RTF columns.
The JSON formatting framework outputs @currentField as text inside the selected elmType.
I propose two possibilities which are not mutually exclusive to improve compatibility:
this elmType would assume the content of the @currentField to be well-formed html, and just use that at the column cell's content.
This selector would treat the contents of the currentfield as well-formed html, and would allow it to be inserted inside an elmType.
Bonus points if the html tree can be traversed using object notation as well.