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Luis Daniel Fernandes Rotger did nice work on showing the imorted imported diagrams using the d3 library
The diagrams are not yet editable.
Perhaps we can offer users support by saving the imported diagrams as SVG graphics (so only use d3 for interpreting and converting) and then implementing a good SVG editor (which can then edit both diagrams and SVG grahics (, e.g., arrows from powerpoint).
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