diff --git a/gramps/gui/widgets/styledtextbuffer.py b/gramps/gui/widgets/styledtextbuffer.py
index 5cbad58e614..5e917e19528 100644
--- a/gramps/gui/widgets/styledtextbuffer.py
+++ b/gramps/gui/widgets/styledtextbuffer.py
@@ -492,7 +492,7 @@ def _remove_style_from_selection(self, style):
         start, end = self._get_selection()
         tags = self._get_tag_from_range(start.get_offset(), end.get_offset())
         for tag_name, tag_data in tags.items():
-            if tag_name.startswith(str(style)):
+            if tag_name is not None and tag_name.startswith(str(style)):
                 for start, end in tag_data:
                     self.remove_tag_by_name(
                         tag_name,