runelite-client: add configuration option for resizable

runelite-client/src/main/java/net/runelite/client/RuneLite.java

@@ -200,6 +200,8 @@ public class RuneLite
 			{
 				gui.setAlwaysOnTop(runeliteConfig.gameAlwaysOnTop());
 			}
+
+			gui.setResizable(runeliteConfig.isResizable());
 		});
 
 		eventBus.post(new ClientUILoaded());

runelite-client/src/main/java/net/runelite/client/config/RuneLiteConfig.java

@@ -44,6 +44,16 @@ public interface RuneLiteConfig extends Config
 		return Constants.GAME_FIXED_SIZE;
 	}
 
+	@ConfigItem(
+		keyName = "isResizable",
+		name = "Enable window resizing",
+		description = "Determines if the window is resizable"
+	)
+	default boolean isResizable()
+	{
+		return true;
+	}
+
 	@ConfigItem(
 		keyName = "uiEnableCustomChrome",
 		name = "Enable custom window chrome",

runelite-client/src/main/java/net/runelite/client/ui/ClientUI.java

@@ -245,6 +245,14 @@ public class ClientUI extends JFrame
 			}
 		}
 
+		if (event.getKey().equals("isResizable"))
+		{
+			SwingUtilities.invokeLater(() ->
+			{
+				this.setResizable(Boolean.valueOf(event.getNewValue()));
+			});
+		}
+
 		if (!event.getKey().equals("gameSize"))
 		{
 			return;