@Override
				public boolean isAddToPopup(ActionContext context) {
					Object contextObject = context.getContextObject();
					if (!(contextObject == outgoingTree || contextObject == incomingTree)) {
						return false;
					}
					return true;
				}
A variable used to restrict open-ended operations, like expanding all nodes or filtering.
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/calltree/CallTreeProvider.java