diff --git a/src/calibre/gui2/tweak_book/editor/widget.py b/src/calibre/gui2/tweak_book/editor/widget.py
index b5b2370f80..d07b7027f7 100644
--- a/src/calibre/gui2/tweak_book/editor/widget.py
+++ b/src/calibre/gui2/tweak_book/editor/widget.py
@@ -384,7 +384,7 @@ class Editor(QMainWindow):
         a = m.addAction
         c = self.editor.cursorForPosition(pos)
         r = self.editor.syntax_range_for_cursor(c)
-        if r.format.property(SPELL_PROPERTY).toBool():
+        if r is not None and r.format.property(SPELL_PROPERTY).toBool():
             word = self.editor.text_for_range(c.block(), r)
             locale = self.editor.spellcheck_locale_for_cursor(c)
             orig_pos = c.position()