diff --git a/spyder/api/shortcuts.py b/spyder/api/shortcuts.py
index fa0005aa80a..e00fc041b08 100644
--- a/spyder/api/shortcuts.py
+++ b/spyder/api/shortcuts.py
@@ -142,8 +142,14 @@ def register_shortcut_for_widget(
         name = name.lower()
         context = context.lower()
 
-        # Add observer to register shortcut when its associated option is
-        # broadcasted by CONF or updated in Preferences.
+        # Register shortcurt for widget
+        keystr = self.get_shortcut(name, context, plugin_name)
+        self._register_shortcut(
+            keystr, name, triggered, context, widget, plugin_name
+        )
+
+        # Add observer for shortcut so that it's updated when changed by users
+        # in Preferences
         config_observer = functools.partial(
             self._register_shortcut,
             name=name,
@@ -200,6 +206,14 @@ def _register_shortcut(
         # Disable current shortcut, if available
         current_shortcut = self._shortcuts.get((context, name, plugin_name))
         if current_shortcut:
+            # Don't do the rest if we're trying to register the same shortcut
+            # again. This happens at startup because shortcuts are registered
+            # on widget creation and then the observer attached to the shortcut
+            # tries to do it again after CONF.notify_all_observers() is called.
+            if current_shortcut.key().toString() == keystr:
+                return
+
+            # Disable current shortcut to create a new one below
             current_shortcut.setEnabled(False)
             current_shortcut.deleteLater()
             self._shortcuts.pop((context, name, plugin_name))
diff --git a/spyder/app/tests/test_mainwindow.py b/spyder/app/tests/test_mainwindow.py
index 075fa33c126..f977b90c2a0 100644
--- a/spyder/app/tests/test_mainwindow.py
+++ b/spyder/app/tests/test_mainwindow.py
@@ -5375,10 +5375,6 @@ def test_copy_paste(main_window, qtbot, tmpdir):
     code_editor = main_window.editor.get_focus_widget()
     code_editor.set_text(code)
 
-    # Register codeeditor shortcuts
-    CONF.notify_section_all_observers("shortcuts")
-    qtbot.wait(300)
-
     # Test copy
     cursor = code_editor.textCursor()
     cursor.setPosition(69)
diff --git a/spyder/plugins/editor/widgets/codeeditor/tests/conftest.py b/spyder/plugins/editor/widgets/codeeditor/tests/conftest.py
index 4879310d406..edb89b9cd0e 100644
--- a/spyder/plugins/editor/widgets/codeeditor/tests/conftest.py
+++ b/spyder/plugins/editor/widgets/codeeditor/tests/conftest.py
@@ -149,10 +149,6 @@ def mock_completions_codeeditor(qtbot_module, request):
     qtbot_module.addWidget(editor)
     editor.show()
 
-    # Register shortcuts for CodeEditor
-    CONF.notify_section_all_observers("shortcuts")
-    qtbot_module.wait(300)
-
     mock_response = Mock()
 
     def perform_request(lang, method, params):
@@ -186,10 +182,6 @@ def completions_codeeditor(completion_plugin_all_started, qtbot_module,
     completion_plugin, capabilities = completion_plugin_all_started
     completion_plugin.wait_for_ms = 2000
 
-    # Register shortcuts for CodeEditor
-    CONF.notify_section_all_observers("shortcuts")
-    qtbot_module.wait(300)
-
     CONF.set('completions', 'enable_code_snippets', False)
     completion_plugin.after_configuration_update([])
     CONF.notify_section_all_observers('completions')
@@ -257,10 +249,6 @@ def codeeditor(qtbot):
     widget.resize(640, 480)
     widget.show()
 
-    # Register shortcuts for CodeEditor
-    CONF.notify_section_all_observers("shortcuts")
-    qtbot.wait(300)
-
     yield widget
     widget.close()
 
diff --git a/spyder/plugins/editor/widgets/codeeditor/tests/test_codeeditor.py b/spyder/plugins/editor/widgets/codeeditor/tests/test_codeeditor.py
index 405abce2e05..0d6ca09635f 100644
--- a/spyder/plugins/editor/widgets/codeeditor/tests/test_codeeditor.py
+++ b/spyder/plugins/editor/widgets/codeeditor/tests/test_codeeditor.py
@@ -721,6 +721,9 @@ def test_shortcut_for_widget_is_updated(config_dialog, codeeditor, qtbot):
     text = ('aa\nbb\ncc\ndd\n')
     editor.set_text(text)
 
+    # We need to wait for a bit so shortcuts are registered correctly
+    qtbot.wait(300)
+
     # Check shortcuts were registered
     assert editor._shortcuts != {}
 
diff --git a/spyder/plugins/editor/widgets/editorstack/tests/test_shortcuts.py b/spyder/plugins/editor/widgets/editorstack/tests/test_shortcuts.py
index 7a704ccf15e..8a5df73b4bc 100644
--- a/spyder/plugins/editor/widgets/editorstack/tests/test_shortcuts.py
+++ b/spyder/plugins/editor/widgets/editorstack/tests/test_shortcuts.py
@@ -42,8 +42,7 @@ def editorstack(qtbot):
     editorstack.show()
     editorstack.go_to_line(1)
 
-    # Register shortcuts
-    CONF.notify_section_all_observers("shortcuts")
+    # We need to wait for a bit so shortcuts are registered correctly
     qtbot.wait(300)
 
     return editorstack
@@ -344,6 +343,27 @@ def test_builtin_undo_redo(editorstack, qtbot):
     assert editor.toPlainText() == 'Something\nLine1\nLine2\nLine3\nLine4\n'
 
 
+@pytest.mark.skipif(
+    sys.platform.startswith("linux") and running_in_ci(),
+    reason='Fails on Linux and CI'
+)
+def test_shortcuts_for_new_editors(editorstack, qtbot):
+    """
+    Test that widget shortcuts are working for new editors.
+
+    This is a regression test for spyder-ide/spyder#23151.
+    """
+    # Create new file and give it focus
+    editorstack.new('bar.py', 'utf-8', 'Line5\nLine6\nLine7\nLine8')
+    editorstack.tabs.setCurrentIndex(1)
+
+    # Go to its first line, click the shortcut to comment it and check it was
+    editorstack.go_to_line(1)
+    editor = editorstack.get_current_editor()
+    qtbot.keyClick(editor, Qt.Key_1, modifier=Qt.ControlModifier)
+    assert editor.toPlainText() == '# Line5\nLine6\nLine7\nLine8\n'
+
+
 if __name__ == "__main__":
     import os
     pytest.main(['-x', os.path.basename(__file__), '-vv', '-rw'])