diff --git a/indra/newview/app_settings/settings.xml b/indra/newview/app_settings/settings.xml
index 33dd0656ed..4982c48141 100644
--- a/indra/newview/app_settings/settings.xml
+++ b/indra/newview/app_settings/settings.xml
@@ -24130,6 +24130,17 @@ Change of this parameter will affect the layout of buttons in notification toast
       <key>Value</key>
       <integer>1</integer>
     </map>
+  <key>FSMaxPendingIMMessages</key>
+  <map>
+    <key>Comment</key>
+    <string>Maxmimum number of pending IM or group messages before a minimized or not visible chat window will be updated</string>
+    <key>Persist</key>
+    <integer>1</integer>
+    <key>Type</key>
+    <string>S32</string>
+    <key>Value</key>
+    <integer>25</integer>
+  </map>
   </map>
 </llsd>
 
diff --git a/indra/newview/fsfloaterim.cpp b/indra/newview/fsfloaterim.cpp
index 7e78c1dea4..1fefb9e259 100644
--- a/indra/newview/fsfloaterim.cpp
+++ b/indra/newview/fsfloaterim.cpp
@@ -87,6 +87,7 @@ FSFloaterIM::FSFloaterIM(const LLUUID& session_id)
 	mControlPanel(NULL),
 	mSessionID(session_id),
 	mLastMessageIndex(-1),
+	mPendingMessages(0),
 	mDialog(IM_NOTHING_SPECIAL),
 	mChatHistory(NULL),
 	mInputEditor(NULL),
@@ -301,8 +302,10 @@ void FSFloaterIM::newIMCallback(const LLSD& data){
 		FSFloaterIM* floater = LLFloaterReg::findTypedInstance<FSFloaterIM>("fs_impanel", session_id);
 		if (floater == NULL) return;
 
-		// update if visible, otherwise will be updated when opened
-		if (floater->getVisible())
+		// update if visible or max pending messages exceeded, otherwise will be updated when opened
+		static LLCachedControl<S32> fsMaxPendingIMMessages(gSavedSettings, "FSMaxPendingIMMessages");
+		floater->mPendingMessages++;
+		if (floater->getVisible() || floater->mPendingMessages > fsMaxPendingIMMessages)
 		{
 			floater->updateMessages();
 		}
@@ -1355,7 +1358,7 @@ void FSFloaterIM::updateMessages()
 	std::list<LLSD> messages;
 
 	// we shouldn't reset unread message counters if IM floater doesn't have focus
-    LLIMModel::instance().getMessages(mSessionID, messages, mLastMessageIndex + 1, hasFocus());
+	LLIMModel::instance().getMessages(mSessionID, messages, mLastMessageIndex + 1, hasFocus());
 
 	if (messages.size())
 	{
@@ -1447,6 +1450,8 @@ void FSFloaterIM::updateMessages()
 			}
 		}
 	}
+
+	mPendingMessages = 0;
 }
 
 void FSFloaterIM::reloadMessages(bool clean_messages/* = false*/)
diff --git a/indra/newview/fsfloaterim.h b/indra/newview/fsfloaterim.h
index 31e228235a..7d4ed99b64 100644
--- a/indra/newview/fsfloaterim.h
+++ b/indra/newview/fsfloaterim.h
@@ -239,6 +239,7 @@ private:
 	FSPanelChatControlPanel* mControlPanel;
 	LLUUID mSessionID;
 	S32 mLastMessageIndex;
+	S32 mPendingMessages;
 
 	EInstantMessage mDialog;
 	LLUUID mOtherParticipantUUID;