Ciao Cepe,
thank you for the hint on filters, I haven't recognized these until now.
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I've played around a bit (with v1.11.2944), but had no success.
In an empty (new) survey, I imported data from PocketTopo (data + sketch). If I draw any other object (e.g. a new cave border in the Border layer), and then create filter with propery "import_source" = "pockettopo",
all objects are filtered - also my "new" object which definitely doesn't have "import_source=pockettopo" (I've checked that in the Properties panel).
The Whiteboard mode looks very interesting though.
Do you have any documentation on that? (in the PDF I haven't found anything)
The imported sketch quality is excellent anyway, it's just at the "wrong" layer
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For me it's perfectly fine if you can import the drawings as generic objects into the sketch layer.