diff --git a/spyder/plugins/editor/widgets/codeeditor/codeeditor.py b/spyder/plugins/editor/widgets/codeeditor/codeeditor.py
index 241bbdc63b6..86637edd7c9 100644
--- a/spyder/plugins/editor/widgets/codeeditor/codeeditor.py
+++ b/spyder/plugins/editor/widgets/codeeditor/codeeditor.py
@@ -774,6 +774,7 @@ def _on_cursor_blinktimer_timeout(self):
     @Slot(QPaintEvent)
     def paint_cursors(self, event):
         """Paint all cursors"""
+        # TODO Critical: timer and cursor width sync with multiple editorstacks
         if self.overwrite_mode:
             font = self.textCursor().block().charFormat().font()
             cursor_width = QFontMetrics(font).horizontalAdvance(" ")
diff --git a/spyder/plugins/editor/widgets/editorstack/editorstack.py b/spyder/plugins/editor/widgets/editorstack/editorstack.py
index c57e565e250..6ef3105ab98 100644
--- a/spyder/plugins/editor/widgets/editorstack/editorstack.py
+++ b/spyder/plugins/editor/widgets/editorstack/editorstack.py
@@ -351,6 +351,7 @@ def __init__(self, parent, actions, use_switcher=True):
         self.remove_trailing_newlines = False
         self.convert_eol_on_save = False
         self.convert_eol_on_save_to = 'LF'
+        self.multicursor_support = True
         self.create_new_file_if_empty = True
         self.indent_guides = False
         self.__file_status_flag = False