diff --git a/OpenRA.Mods.Common/UpdateRules/Rules/ConvertSupportPowerRangesToFootprint.cs b/OpenRA.Mods.Common/UpdateRules/Rules/ConvertSupportPowerRangesToFootprint.cs
new file mode 100644
index 0000000000..85c6deeeca
--- /dev/null
+++ b/OpenRA.Mods.Common/UpdateRules/Rules/ConvertSupportPowerRangesToFootprint.cs
@@ -0,0 +1,102 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2020 The OpenRA Developers (see AUTHORS)
+ * This file is part of OpenRA, which is free software. It is made
+ * available to you under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version. For more
+ * information, see COPYING.
+ */
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace OpenRA.Mods.Common.UpdateRules.Rules
+{
+	public class ConvertSupportPowerRangesToFootprint : UpdateRule
+	{
+		public override string Name { get { return "Convert support power ranges to footprint"; } }
+		public override string Description
+		{
+			get
+			{
+				return "ChronoshiftPower and GrantExternalConditionPower use footprint areas\n" +
+				"instead of a circular range and they no longer have a fallback default area value.\n" +
+				"The old Range values will be converted to footprints as part of this update.";
+			}
+		}
+
+		static readonly string[] AffectedTraits = new string[] { "GrantExternalConditionPower", "ChronoshiftPower" };
+
+		public override IEnumerable<string> UpdateActorNode(ModData modData, MiniYamlNode actorNode)
+		{
+			foreach (var at in AffectedTraits)
+				foreach (var trait in actorNode.ChildrenMatching(at))
+					UpdatePower(trait);
+
+			yield break;
+		}
+
+		void UpdatePower(MiniYamlNode power)
+		{
+			var range = 1;
+			var rangeNode = power.LastChildMatching("Range");
+			if (rangeNode != null)
+			{
+				range = rangeNode.NodeValue<int>();
+				if (range > 3)
+					locations.Add("{0} ({1})".F(rangeNode.Key, rangeNode.Location.Filename));
+
+				power.RemoveNode(rangeNode);
+			}
+
+			var size = 2 * range + 1;
+			power.AddNode(new MiniYamlNode("Dimensions", size.ToString() + ", " + size.ToString()));
+
+			var footprint = string.Empty;
+
+			var emptycell = range;
+			var affectedcell = 1;
+
+			for (var i = 0; i < size; i++)
+			{
+				for (var e = 0; e < emptycell; e++)
+					footprint += '_';
+
+				for (var a = 0; a < affectedcell; a++)
+					footprint += 'x';
+
+				for (var e = 0; e < emptycell; e++)
+					footprint += '_';
+
+				if (i < range)
+				{
+					emptycell--;
+					affectedcell += 2;
+				}
+				else
+				{
+					emptycell++;
+					affectedcell -= 2;
+				}
+
+				footprint += ' ';
+			}
+
+			power.AddNode(new MiniYamlNode("Footprint", footprint));
+		}
+
+		readonly List<string> locations = new List<string>();
+
+		public override IEnumerable<string> AfterUpdate(ModData modData)
+		{
+			if (locations.Any())
+				yield return "Please check and adjust the new auto-generated dimensions.\n" +
+					UpdateUtils.FormatMessageList(locations);
+
+			locations.Clear();
+		}
+	}
+}
diff --git a/OpenRA.Mods.Common/UpdateRules/UpdatePath.cs b/OpenRA.Mods.Common/UpdateRules/UpdatePath.cs
index 9578041794..80b4e2e98e 100644
--- a/OpenRA.Mods.Common/UpdateRules/UpdatePath.cs
+++ b/OpenRA.Mods.Common/UpdateRules/UpdatePath.cs
@@ -63,6 +63,7 @@ namespace OpenRA.Mods.Common.UpdateRules
 				new RenameWithNukeLaunch(),
 				new SpawnActorPowerDefaultEffect(),
 				new RemoveConditionManager(),
+				new ConvertSupportPowerRangesToFootprint(),
 			})
 		};