1. When importing data from the Import Spreasdsheet, edges that connect a node to itself can be imported as a directed edge. However, the degree metric for this node counts both the outbound edge and the inbound edge separately, resulting in a degree count of 2.

2. When importing data from text with a type field set to Undirected, edges that connect a node to itself are imported as type Directed (other edges are typed Undirected as expected). I am unable to change the type of an edge with the right-click Edit Edge function.

3. When I attempt to add an edge with the Add Edge function, the dialog arranges the node dropdowns so that the same node is never available for both source and target.

source: https://forum.gephi.org/viewtopic.php?t=2263&p=7537#p7537