diff --git a/indra/newview/fsfloaterim.cpp b/indra/newview/fsfloaterim.cpp
index 2d9a6019b9..f1d7ac28fb 100644
--- a/indra/newview/fsfloaterim.cpp
+++ b/indra/newview/fsfloaterim.cpp
@@ -76,6 +76,7 @@
 
 #include "llnotificationtemplate.h"		// <FS:Zi> Viewer version popup
 #include "fscommon.h"
+#include "fsfloaternearbychat.h"
 
 floater_showed_signal_t FSFloaterIM::sIMFloaterShowedSignal;
 
@@ -1520,7 +1521,6 @@ void FSFloaterIM::processChatHistoryStyleUpdate(const LLSD& newvalue)
 			floater->mInputEditor->setFont(font);
 		}
 	}
-
 }
 
 void FSFloaterIM::processSessionUpdate(const LLSD& session_update)
@@ -1875,6 +1875,28 @@ void FSFloaterIM::setEnableAddFriendButton(BOOL enabled)
 }
 // </FS:Ansariel>
 
+// <FS:CR> FIRE-11734
+//static
+void FSFloaterIM::clearAllOpenHistories()
+{
+	LLFloaterReg::const_instance_list_t& inst_list = LLFloaterReg::getFloaterList("fs_impanel");
+	for (LLFloaterReg::const_instance_list_t::const_iterator iter = inst_list.begin();
+		 iter != inst_list.end(); ++iter)
+	{
+		FSFloaterIM* floater = dynamic_cast<FSFloaterIM*>(*iter);
+		if (floater)
+		{
+			floater->reloadMessages(true);
+		}
+	}
+	
+	FSFloaterNearbyChat* nearby_chat = LLFloaterReg::getTypedInstance<FSFloaterNearbyChat>("fs_nearby_chat", LLSD());
+	if (nearby_chat)
+	{
+		nearby_chat->reloadMessages(true);
+	}
+}
+
 void FSFloaterIM::initIMSession(const LLUUID& session_id)
 {
 	// Change the floater key to bind it to a new session.
diff --git a/indra/newview/fsfloaterim.h b/indra/newview/fsfloaterim.h
index 69266585ef..c7f5cc29ac 100644
--- a/indra/newview/fsfloaterim.h
+++ b/indra/newview/fsfloaterim.h
@@ -116,6 +116,8 @@ public:
 
 	void updateChatHistoryStyle();
 	static void processChatHistoryStyleUpdate(const LLSD& newvalue);
+	
+	static void clearAllOpenHistories();	// <FS:CR> FIRE-11734
 
 	BOOL handleDragAndDrop(S32 x, S32 y, MASK mask,
 							   BOOL drop, EDragAndDropType cargo_type,
diff --git a/indra/newview/lllogchat.cpp b/indra/newview/lllogchat.cpp
index 846b5ee526..20480f4241 100755
--- a/indra/newview/lllogchat.cpp
+++ b/indra/newview/lllogchat.cpp
@@ -672,10 +672,10 @@ void LLLogChat::deleteTranscripts()
 			}			
 		}
 	}
-
-	// <FS:CR> Firestorm communications UI
+	
+	// <FS:CR> FIRE-11734 - Flush out the current histories from any open chat window
 	//LLFloaterIMSessionTab::processChatHistoryStyleUpdate(true);
-	FSFloaterIM::processChatHistoryStyleUpdate(true);
+	FSFloaterIM::clearAllOpenHistories();
 	// </FS:CR>
 }