diff --git a/binaries/data/mods/public/gui/session/session.js b/binaries/data/mods/public/gui/session/session.js
index ce9ef99b27..523f0668c1 100644
--- a/binaries/data/mods/public/gui/session/session.js
+++ b/binaries/data/mods/public/gui/session/session.js
@@ -662,20 +662,19 @@ function onSimulationUpdate()
 	g_EntityStates = {};
 	g_SimState = undefined;
 
+	Engine.ProfileStart("sdf");
+	const info = Engine.GuiInterfaceCall("GetAndClearTemplateChanges");
 	// Templates change depending on technologies and auras, so they have to be reloaded after such a change.
-	// g_TechnologyData data never changes, so it shouldn't be deleted.
-	const players = Engine.GuiInterfaceCall("GetPlayersWithModifiedTemplates");
-	for (const player of players)
-		g_TemplateData[player] = {};
-	if (players.size)
-		Engine.GuiInterfaceCall("ResetPlayersWithModifiedTemplates");
+	// g_TechnologyData data never changes, so it shouldn't be cleared.
+	if (info.playersWithModifiedTemplates)
+		for (const player of info.playersWithModifiedTemplates)
+			g_TemplateData[player] = {};
 
-	// Some changes may require re-rendering the selection.
-	if (Engine.GuiInterfaceCall("IsSelectionDirty"))
-	{
+	// Some changes require reloading some cached values even if the selection itself didn't change.
+	if (info.selectionDirty)
 		g_Selection.onChange();
-		Engine.GuiInterfaceCall("ResetSelectionDirty");
-	}
+
+	Engine.ProfileStop("sdf");
 
 	if (!GetSimState())
 		return;
diff --git a/binaries/data/mods/public/simulation/components/GuiInterface.js b/binaries/data/mods/public/simulation/components/GuiInterface.js
index c61db4b7a4..1aa1ebb71a 100644
--- a/binaries/data/mods/public/simulation/components/GuiInterface.js
+++ b/binaries/data/mods/public/simulation/components/GuiInterface.js
@@ -37,7 +37,7 @@ GuiInterface.prototype.Init = function()
 	this.entsWithAuraAndStatusBars = new Set();
 	this.enabledVisualRangeOverlayTypes = {};
 	this.playersWithModifiedTemplates = new Set();
-	this.selectionDirty = {};
+	this.playersWithDirtySelection = new Set();
 	this.obstructionSnap = new ObstructionSnap();
 };
 
@@ -707,53 +707,50 @@ GuiInterface.prototype.GetNeededResources = function(player, data)
 	return cmpPlayer ? cmpPlayer.GetNeededResources(data.cost) : {};
 };
 
-/**
- * State of the templateData (player dependent): true when some template values have been modified
- * and need to be reloaded by the gui.
- */
 GuiInterface.prototype.OnTemplateModification = function(msg)
 {
+	// The GUI caches templates, which could become out-of-date now, so tell it
+	// to reload all of them for that player.
+	// TODO: Allow the GUI to do that more selectively by passing which values
+	// of which components have changed and letting it only reload the affected
+	// ones.
 	this.playersWithModifiedTemplates.add(msg.player);
-	this.selectionDirty[msg.player] = true;
+
+	this.playersWithDirtySelection.add(msg.player);
 };
 
-GuiInterface.prototype.GetPlayersWithModifiedTemplates = function(player)
-{
-	return this.playersWithModifiedTemplates;
-};
-
-GuiInterface.prototype.ResetPlayersWithModifiedTemplates = function()
-{
-	this.playersWithModifiedTemplates.clear();
-};
-
-/**
- * Some changes may require an update to the selection panel,
- * which is cached for efficiency. Inform the GUI it needs reloading.
- */
 GuiInterface.prototype.OnDisabledTemplatesChanged = function(msg)
 {
-	this.selectionDirty[msg.player] = true;
+	this.playersWithDirtySelection.add(msg.player);
 };
 
 GuiInterface.prototype.OnDisabledTechnologiesChanged = function(msg)
 {
-	this.selectionDirty[msg.player] = true;
+	this.playersWithDirtySelection.add(msg.player);
 };
 
+/**
+ * Some values about the selection (trainable entities for example) are cached
+ * by the GUI. Inform the GUI that it needs to reload them.
+ */
 GuiInterface.prototype.SetSelectionDirty = function(player)
 {
-	this.selectionDirty[player] = true;
+	this.playersWithDirtySelection.add(player);
 };
 
-GuiInterface.prototype.IsSelectionDirty = function(player)
+GuiInterface.prototype.GetAndClearTemplateChanges = function(player)
 {
-	return this.selectionDirty[player] || false;
-};
+	const ret = {};
+	if (this.playersWithModifiedTemplates.size)
+		ret.playersWithModifiedTemplates = new Set(this.playersWithModifiedTemplates);
 
-GuiInterface.prototype.ResetSelectionDirty = function()
-{
-	this.selectionDirty = {};
+	if (this.playersWithDirtySelection.has(player))
+		ret.selectionDirty = true;
+
+	this.playersWithModifiedTemplates.clear();
+	this.playersWithDirtySelection.clear();
+
+	return ret;
 };
 
 /**
@@ -2132,10 +2129,7 @@ GuiInterface.prototype.exposedFunctions = {
 
 	"GetTraderNumber": 1,
 	"GetTradingGoods": 1,
-	"GetPlayersWithModifiedTemplates": 1,
-	"ResetPlayersWithModifiedTemplates": 1,
-	"IsSelectionDirty": 1,
-	"ResetSelectionDirty": 1
+	"GetAndClearTemplateChanges": 1
 };
 
 GuiInterface.prototype.ScriptCall = function(player, name, args)