Nodes menu

deletion

delete nodes

deletes all selected nodes

delete isolates

deletes all nodes without incident links within existing current selection or globally otherwise

selection

select all

adds all nodes to selection

deselect all

removes all nodes from selection

invert selection

removes all nodes from selection and adds those that had not been selected before

select groups

adds all groups to selection

appearance

templates...

opens the node templates dialog

properties...

opens the node properties dialog