private Collection<FGEdge> getCurrentUngroupedEdges() {

		Collection<FGEdge> result = new HashSet<>(getEdges());
		result.removeIf(e -> e.getStart() instanceof GroupedFunctionGraphVertex ||
			e.getEnd() instanceof GroupedFunctionGraphVertex);

		return result;
	}
This method returns all edges known by this class.  This differs from the edges 
returned from {@link Graph} in that those may be a smaller subset of the collection returned
here.  Due to graph manipulation after creation time (e.g., vertex grouping), the 
edges known by the {@link Graph} may not include all edges created at the same time
as the graph and any others created by graph mutating operations <b>that are not the 
result of a grouping operation</b>.

@return all edges known by this class, visible or not.
Ghidra/Features/FunctionGraph/src/main/java/ghidra/app/plugin/core/functiongraph/graph/FunctionGraph.java