diff --git a/src/calibre/gui2/actions/choose_library.py b/src/calibre/gui2/actions/choose_library.py
index 95828f2c5f..a03b3c42de 100644
--- a/src/calibre/gui2/actions/choose_library.py
+++ b/src/calibre/gui2/actions/choose_library.py
@@ -321,9 +321,10 @@ class ChooseLibraryAction(InterfaceAction):
         a.setWhatsThis(tooltip)
 
     def library_changed(self, db):
-        self.prev_lname = self.last_lname
         lname = self.stats.library_used(db)
-        self.last_lname = lname
+        if lname != self.last_lname:
+            self.prev_lname = self.last_lname
+            self.last_lname = lname
         if len(lname) > 16:
             lname = lname[:16] + u'…'
         a = self.qaction