Index: binaries/data/mods/public/gui/session/messages.js
===================================================================
--- binaries/data/mods/public/gui/session/messages.js
+++ binaries/data/mods/public/gui/session/messages.js
@@ -309,6 +309,9 @@
 			colorizePlayernameParameters(notification.parameters);
 		}
 
+		if (notification.chatTimeOut)
+			message.chatTimeOut = notification.chatTimeOut;
+
 		addChatMessage(message);
 	},
 	"defeat": function(notification, player)
@@ -891,7 +894,8 @@
 
 	// Update chat overlay
 	g_ChatMessages.push(formatted);
-	g_ChatTimers.push(setTimeout(removeOldChatMessage, g_ChatTimeout * 1000));
+	let chatTimeOut = msg.chatTimeOut ? +msg.chatTimeOut : g_ChatTimeout;
+	g_ChatTimers.push(setTimeout(removeOldChatMessage, chatTimeOut * 1000));
 
 	if (g_ChatMessages.length > g_ChatLines)
 		removeOldChatMessage();