It is possible to fuse the starting points of two outgoing connections. This results in a duplication. Any resource send out over the first resource will be duplicated and also send out over the second resource (and the third, and the fourth, etc.). This is called resource duplication. For elements like sources and converters duplication is the only way to create multiple outputs. See the examples of duplication above.
To create a duplication in the editor. You need to drag the starting point of a connection over the starting value of another connection. This requires that the first connection has a starting value. Once the duplication is created you can clear the starting value if you wish.