diff --git a/binaries/data/mods/public/gamesettings/GameSettings.js b/binaries/data/mods/public/gamesettings/GameSettings.js
index 0dbe5912f6..e6625ac79c 100644
--- a/binaries/data/mods/public/gamesettings/GameSettings.js
+++ b/binaries/data/mods/public/gamesettings/GameSettings.js
@@ -20,7 +20,7 @@ class GameSettings
 		});
 
 		Object.defineProperty(this, "savegameID", {
-			"value": !!savegameID,
+			"value": savegameID,
 		});
 
 		// Load all possible civ data - don't presume that some will be available.
diff --git a/binaries/data/mods/public/gui/gamesetup/SetupWindow.js b/binaries/data/mods/public/gui/gamesetup/SetupWindow.js
index dda689b971..4dc88cb5ec 100644
--- a/binaries/data/mods/public/gui/gamesetup/SetupWindow.js
+++ b/binaries/data/mods/public/gui/gamesetup/SetupWindow.js
@@ -30,7 +30,7 @@ class SetupWindow
 
 		const mapCache = new MapCache();
 		g_GameSettings = new GameSettings();
-		g_GameSettings.init(mapCache, g_IsController ? savedGame : null);
+		g_GameSettings.init(mapCache, g_IsController ? savedGame : undefined);
 
 
 		let netMessages = new NetMessages();
diff --git a/binaries/data/mods/public/gui/gamesetup_mp/gamesetup_mp.js b/binaries/data/mods/public/gui/gamesetup_mp/gamesetup_mp.js
index 667d86be95..2ae6a5eebf 100644
--- a/binaries/data/mods/public/gui/gamesetup_mp/gamesetup_mp.js
+++ b/binaries/data/mods/public/gui/gamesetup_mp/gamesetup_mp.js
@@ -319,7 +319,7 @@ async function handleAuthenticated(message, loadSavedGame)
 	}
 	g_IsConnecting = false;
 
-	const savegameID = loadSavedGame ? await Engine.PushGuiPage("page_loadgame.xml") : null;
+	const savegameID = loadSavedGame ? await Engine.PushGuiPage("page_loadgame.xml") : undefined;
 
 	if (loadSavedGame && !savegameID)
 	{
@@ -329,7 +329,7 @@ async function handleAuthenticated(message, loadSavedGame)
 	}
 
 	Engine.SwitchGuiPage("page_gamesetup.xml", {
-		"savedGame": savegameID ?? message.savedGame,
+		"savedGame": savegameID, // Undefined or the savegame ID
 		"serverName": g_ServerName,
 		"hasPassword": g_ServerHasPassword
 	});
diff --git a/source/network/scripting/JSInterface_Network.cpp b/source/network/scripting/JSInterface_Network.cpp
index f0acf1730a..ba5162521d 100644
--- a/source/network/scripting/JSInterface_Network.cpp
+++ b/source/network/scripting/JSInterface_Network.cpp
@@ -283,7 +283,7 @@ void StartNetworkGame(const ScriptInterface& scriptInterface, JS::HandleValue sa
 	JS::RootedValue attribs(rq.cx, attribs1);
 	std::string attributesAsString{Script::StringifyJSON(rq, &attribs)};
 
-	if (savegame.isFalse())
+	if (savegame.isUndefined())
 	{
 		g_NetClient->SendStartGameMessage(attributesAsString);
 		return;