diff --git a/src/Mod/Path/PathScripts/PathFeatureExtensionsGui.py b/src/Mod/Path/PathScripts/PathFeatureExtensionsGui.py
index bc8f88d865..b133c80aff 100644
--- a/src/Mod/Path/PathScripts/PathFeatureExtensionsGui.py
+++ b/src/Mod/Path/PathScripts/PathFeatureExtensionsGui.py
@@ -194,6 +194,7 @@ class TaskPanelExtensionPage(PathOpGui.TaskPanelPage):
         self.extensionsCache = dict()
         self.extensionsReady = False
         self.enabled = True
+        self.lastDefaultLength = ""
 
         self.extensions = list()
 
@@ -284,6 +285,7 @@ class TaskPanelExtensionPage(PathOpGui.TaskPanelPage):
         self._initializeExtensions(obj)  # Efficiently initialize Extensions
         self.defaultLength.updateSpinBox()
         self._getUseOutlineState()  # Find `useOutline` checkbox and get its boolean value
+        self.lastDefaultLength = self.form.defaultLength.text()  # set last DL value
         self.fieldsSet = True  # flag to identify initial values set
 
     def _initializeExtensions(self, obj):
@@ -299,13 +301,13 @@ class TaskPanelExtensionPage(PathOpGui.TaskPanelPage):
             self.form.extensionEdit.setDisabled(True)
         self.setExtensions(self.extensions)
 
-    def updateQuantitySpinBoxes(self, index=None):
-        prevValue = self.form.defaultLength.text()
+    def _applyDefaultLengthChange(self, index=None):
+        """_applyDefaultLengthChange(index=None)...
+        Helper method to update Default Length spinbox,
+        and update extensions due to change in Default Length."""
         self.defaultLength.updateSpinBox()
-        postValue = self.form.defaultLength.text()
-
-        if postValue != prevValue:
-            PathLog.debug("updateQuantitySpinBoxes() post != prev value")
+        if self.form.defaultLength.text() != self.lastDefaultLength:
+            self.lastDefaultLength = self.form.defaultLength.text()
             self._resetCachedExtensions()  # Reset extension cache because extension dimensions likely changed
             self._enableExtensions()  # Recalculate extensions
 
@@ -490,7 +492,7 @@ class TaskPanelExtensionPage(PathOpGui.TaskPanelPage):
             if self.fieldsSet:
                 if self.form.enableExtensions.isChecked():
                     if prop == "ExtensionLengthDefault":
-                        self.updateQuantitySpinBoxes()
+                        self._applyDefaultLengthChange()
                     elif prop == "Base":
                         self.extensionsReady = False
                         self.setExtensions(FeatureExtensions.getExtensions(obj))
@@ -625,8 +627,8 @@ class TaskPanelExtensionPage(PathOpGui.TaskPanelPage):
         self.form.buttonClear.clicked.connect(self.extensionsClear)
         self.form.buttonDisable.clicked.connect(self.extensionsDisable)
         self.form.buttonEnable.clicked.connect(self.extensionsEnable)
-        self.form.defaultLength.editingFinished.connect(self.updateQuantitySpinBoxes)
         self.form.enableExtensions.toggled.connect(self._enableExtensions)
+        self.form.defaultLength.editingFinished.connect(self._applyDefaultLengthChange)
 
         self.model.itemChanged.connect(self.updateItemEnabled)
 
diff --git a/src/Mod/Path/PathScripts/PathGui.py b/src/Mod/Path/PathScripts/PathGui.py
index a39f506c4f..bc825bc2ce 100644
--- a/src/Mod/Path/PathScripts/PathGui.py
+++ b/src/Mod/Path/PathScripts/PathGui.py
@@ -125,14 +125,29 @@ class QuantitySpinBox(QtCore.QObject):
         self.onBeforeChange = onBeforeChange
         self.prop = None
         self.obj = obj
+        self.lastWidgetText = self.widget.text()
         self.attachTo(obj, prop)
         self.widget.installEventFilter(self)
+        # Connect local class method as slot
+        self.widget.textChanged.connect(self.onWidgetValueChanged)
 
     def eventFilter(self, obj, event):
         if event.type() == QtCore.QEvent.Type.FocusIn:
             self.updateSpinBox()
         return False
 
+    def onWidgetValueChanged(self):
+        """onWidgetValueChanged()... Slot method for determining if a change
+        in widget value is a result of an expression edit, or a simple spinbox change.
+        If the former, emit a manual `editingFinished` signal because the Formula Editor
+        window returned a value to the base widget, leaving it in read-only mode,
+        and finishing the editing of the value. Otherwise, due nothing if the value
+        has not changed, or there is no active expression for the property.
+        If the user closes the Formula Editor to cancel the edit, the value will not
+        be changed, and this manual signal will not be emitted."""
+        if self._hasExpression() and self.widget.text() != self.lastWidgetText:
+            self.widget.editingFinished.emit()
+
     def attachTo(self, obj, prop=None):
         """attachTo(obj, prop=None) ... use an existing editor for the given object and property"""
         PathLog.track(self.prop, prop)
@@ -180,6 +195,7 @@ class QuantitySpinBox(QtCore.QObject):
                     quantity = PathUtil.getProperty(self.obj, self.prop)
             value = quantity.Value if hasattr(quantity, "Value") else quantity
             self.widget.setProperty("rawValue", value)
+            self.lastWidgetText = self.widget.text()  # update last widget value
             if expr:
                 self.widget.setReadOnly(True)
                 self.widget.setStyleSheet("color: gray")