diff --git a/src/calibre/gui2/convert/search_and_replace.py b/src/calibre/gui2/convert/search_and_replace.py
index 6fc6c5ec78..2a5314eabf 100644
--- a/src/calibre/gui2/convert/search_and_replace.py
+++ b/src/calibre/gui2/convert/search_and_replace.py
@@ -167,14 +167,7 @@ class SearchAndReplaceWidget(Widget, Ui_Form):
     def break_cycles(self):
         Widget.break_cycles(self)
 
-        def d(x):
-            try:
-                x.disconnect()
-            except Exception:
-                pass
-
-        d(self.sr_search)
-
+        self.sr_search.doc_update.disconnect(self.update_doc)
         self.sr_search.break_cycles()
 
     def update_doc(self, doc):