GP-5235 - Decompiler - Fixed middle-mouse bug when moving to a new

function

Ghidra/Features/Decompiler/src/main/java/ghidra/app/decompiler/component/DecompilerPanel.java

@@ -419,7 +419,9 @@ public class DecompilerPanel extends JPanel implements FieldMouseListener, Field
 
 		// Apply the new middle-mouse highlighter when we have rebuilt the token
 		controller.doWhenNotBusy(() -> {
-			activeMiddleMouse.apply();
+			if (activeMiddleMouse != null) {
+				activeMiddleMouse.apply();
+			}
 		});
 	}
 
@@ -512,6 +514,11 @@ public class DecompilerPanel extends JPanel implements FieldMouseListener, Field
 			return;
 		}
 
+		if (activeMiddleMouse != null) {
+			activeMiddleMouse.clear();
+			activeMiddleMouse = null;
+		}
+
 		DecompileData oldData = this.decompileData;
 		this.decompileData = decompileData;
 		Function function = decompileData.getFunction();