Hello
Affected code is
using netDxf;
using netDxf.Entities;
var invalid = new DxfDocument();
var text = new Text("Multiply\nrows\ntext");
invalid.Entities.Add(text);
invalid.Save("invalid.dxf");
var valid = new DxfDocument();
text = new Text("One row text");
valid.Entities.Add(text);
valid.Save("valid.dxf");
The first one should throw an Argument exception because text entity does not support multiple rows.