diff --git a/source/blender/editors/curves/intern/curves_pen.cc b/source/blender/editors/curves/intern/curves_pen.cc
index 188a8bbd4aa..3da8288201d 100644
--- a/source/blender/editors/curves/intern/curves_pen.cc
+++ b/source/blender/editors/curves/intern/curves_pen.cc
@@ -479,7 +479,9 @@ static bool move_handles_in_curve(const PenToolOperation &ptd,
       offset = snap_8_angles(offset);
     }
 
-    if (ptd.point_added) {
+    /* Set both handles to be `Aligned` if this point is newly added or is
+     * no longer control freely. */
+    if (ptd.point_added || ptd.handle_moved) {
       handle_types_left[point_i] = BEZIER_HANDLE_ALIGN;
       handle_types_right[point_i] = BEZIER_HANDLE_ALIGN;
     }
@@ -1181,6 +1183,8 @@ wmOperatorStatus PenToolOperation::invoke(bContext *C, wmOperator *op, const wmE
   this->move_entire = false;
   this->snap_angle = false;
 
+  this->handle_moved = false;
+
   if (!(ELEM(event->type, LEFTMOUSE) && ELEM(event->val, KM_PRESS, KM_DBL_CLICK))) {
     return OPERATOR_RUNNING_MODAL;
   }
@@ -1223,6 +1227,11 @@ wmOperatorStatus PenToolOperation::modal(bContext *C, wmOperator *op, const wmEv
     }
     else if (event->val == int(PenModal::MoveHandle)) {
       this->move_handle = !this->move_handle;
+
+      /* Record if handle has every been moved. */
+      if (this->move_handle) {
+        this->handle_moved = true;
+      }
     }
   }
 
diff --git a/source/blender/editors/include/ED_curves.hh b/source/blender/editors/include/ED_curves.hh
index 5fe9f5e1232..b2a599fb03b 100644
--- a/source/blender/editors/include/ED_curves.hh
+++ b/source/blender/editors/include/ED_curves.hh
@@ -91,6 +91,8 @@ class PenToolOperation {
 
   bool point_added;
   bool point_removed;
+  /* Used to go back to `aligned` after `move_handle` becomes `false` */
+  bool handle_moved;
 
   float4x4 projection;
   float2 mouse_co;
diff --git a/tests/files/animation/vertex_groups.blend b/tests/files/animation/vertex_groups.blend
new file mode 100644
index 00000000000..f8479f00f1d
--- /dev/null
+++ b/tests/files/animation/vertex_groups.blend
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:d22b1a372530a0feddd3456eb25e60e12af60c014fd6b15a19ef8cdb504f7749
+size 98575
diff --git a/tests/python/CMakeLists.txt b/tests/python/CMakeLists.txt
index 27dda2c6bad..e6ea98f6a5e 100644
--- a/tests/python/CMakeLists.txt
+++ b/tests/python/CMakeLists.txt
@@ -608,6 +608,13 @@ if(TEST_SRC_DIR_EXISTS)
     --
     --testdir "${TEST_SRC_DIR}/animation"
   )
+
+  add_blender_test(
+    vertex_group_painting
+    --python ${CMAKE_CURRENT_LIST_DIR}/vertex_group_painting.py
+    --
+    --testdir "${TEST_SRC_DIR}/animation"
+  )
 endif()
 
 # ------------------------------------------------------------------------------
diff --git a/tests/python/vertex_group_painting.py b/tests/python/vertex_group_painting.py
new file mode 100644
index 00000000000..b89e5e65870
--- /dev/null
+++ b/tests/python/vertex_group_painting.py
@@ -0,0 +1,76 @@
+# SPDX-FileCopyrightText: 2025 Blender Authors
+#
+# SPDX-License-Identifier: GPL-2.0-or-later
+
+import unittest
+import sys
+import pathlib
+
+import bpy
+
+"""
+blender -b --factory-startup --python tests/python/vertex_group_paint.py -- --testdir tests/files/animation/
+"""
+
+
+class NormalizeAllTest(unittest.TestCase):
+    """Test for normalizing all vertex groups on a mesh."""
+
+    def setUp(self) -> None:
+        bpy.ops.wm.read_homefile(use_factory_startup=True)
+        self._load_test_file()
+
+        # Make sure the initial state is what we expect/need for the tests.
+        self.cube = bpy.data.objects['Cube']
+        self.assertEqual(bpy.context.active_object, self.cube)
+        self.assertEqual(len(self.cube.vertex_groups), 2)
+
+    def _load_test_file(self):
+        blendpath = str(args.testdir / "vertex_groups.blend")
+        bpy.ops.wm.read_homefile(use_factory_startup=True)  # Just to be sure.
+        bpy.ops.wm.open_mainfile(filepath=blendpath, load_ui=False)
+
+    def test_normalize_all(self):
+        # Initial state.
+        self.cube.data.vertices[0].groups[0].weight = 0.375
+        self.cube.data.vertices[0].groups[1].weight = 0.125
+        self.cube.vertex_groups[0].lock_weight = False
+        self.cube.vertex_groups[1].lock_weight = False
+
+        # Attempt to normalize all vertex groups.  Should succeed.
+        bpy.ops.object.vertex_group_normalize_all(group_select_mode='ALL', lock_active=False)
+        self.assertEqual(self.cube.data.vertices[0].groups[0].weight, 0.75)
+        self.assertEqual(self.cube.data.vertices[0].groups[1].weight, 0.25)
+
+    def test_normalize_all_locked(self):
+        # Initial state.
+        self.cube.data.vertices[0].groups[0].weight = 0.375
+        self.cube.data.vertices[0].groups[1].weight = 0.125
+        self.cube.vertex_groups[0].lock_weight = True
+        self.cube.vertex_groups[1].lock_weight = True
+
+        # Attempt to normalize all vertex groups.  Should fail, leaving the weights as-is.
+        with self.assertRaises(RuntimeError):
+            bpy.ops.object.vertex_group_normalize_all(group_select_mode='ALL', lock_active=False)
+        self.assertEqual(self.cube.data.vertices[0].groups[0].weight, 0.375)
+        self.assertEqual(self.cube.data.vertices[0].groups[1].weight, 0.125)
+
+
+def main():
+    global args
+    import argparse
+
+    if '--' in sys.argv:
+        argv = [sys.argv[0]] + sys.argv[sys.argv.index('--') + 1:]
+    else:
+        argv = sys.argv
+
+    parser = argparse.ArgumentParser()
+    parser.add_argument('--testdir', required=True, type=pathlib.Path)
+    args, remaining = parser.parse_known_args(argv)
+
+    unittest.main(argv=remaining)
+
+
+if __name__ == "__main__":
+    main()