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If we select a node with multiple downstream nodes and add from the quick add menu, we make a single connection (if possible) from the selected node to the inserted node and continue the multiple paths from that node's output. Take the below scenario as an example:
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Inserting another blur node here results in the following:
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If we were to select only a wire from the above multiple outputs however, the inserted node would only connect through that wire. Here is what happens if we inserted the same node but the wire to gradient removal was selected instead of the blur node:
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6 - Inserting positions.
If a new node can't be placed next to the selected node (the space is occupied by downstream nodes), then node will be placed above or below the current selection.
7 - Multiple selection
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