diff -r d7e0ddb5974b -r c001c373f66c controls/DebugVariablePanel/DebugVariableItem.py
--- a/controls/DebugVariablePanel/DebugVariableItem.py	Fri Oct 08 09:11:55 2021 +0200
+++ b/controls/DebugVariablePanel/DebugVariableItem.py	Fri Oct 08 09:13:02 2021 +0200
@@ -144,7 +144,7 @@
         """
         # Return immediately if data empty or none
         if self.Data is None or self.Data.count == 0:
-            return None
+            return []
 
         # Find nearest data outside given range indexes
         start_idx = (self.GetNearestData(start_tick, -1)