diff --git a/src/calibre/gui2/tweak_book/editor/text.py b/src/calibre/gui2/tweak_book/editor/text.py
index ba28bbf013..0dbc268bef 100644
--- a/src/calibre/gui2/tweak_book/editor/text.py
+++ b/src/calibre/gui2/tweak_book/editor/text.py
@@ -7,6 +7,7 @@ __license__ = 'GPL v3'
 __copyright__ = '2013, Kovid Goyal <kovid at kovidgoyal.net>'
 
 import re, importlib
+from collections import deque
 import textwrap, unicodedata
 from future_builtins import map
 
@@ -103,6 +104,7 @@ class TextEdit(PlainTextEdit):
         self.cursorPositionChanged.connect(self.highlight_cursor_line)
         self.blockCountChanged[int].connect(self.update_line_number_area_width)
         self.updateRequest.connect(self.update_line_number_area)
+        self.currently_showing_tooltip_memory = deque(maxlen=10)
 
     @dynamic_property
     def is_modified(self):
@@ -648,9 +650,11 @@ class TextEdit(PlainTextEdit):
         if fmt is not None:
             tt = unicode(fmt.toolTip())
             if tt:
+                tt = textwrap.fill(tt)
+                self.currently_showing_tooltip_memory.append(tt)
                 QToolTip.setFont(self.tooltip_font)
                 QToolTip.setPalette(self.tooltip_palette)
-                QToolTip.showText(ev.globalPos(), textwrap.fill(tt))
+                QToolTip.showText(ev.globalPos(), tt)
                 return
         QToolTip.hideText()
         ev.ignore()