diff --git a/src/Gui/ExpressionCompleter.cpp b/src/Gui/ExpressionCompleter.cpp
index f10975f1e9..59c53db1c8 100644
--- a/src/Gui/ExpressionCompleter.cpp
+++ b/src/Gui/ExpressionCompleter.cpp
@@ -1013,7 +1013,7 @@ void ExpressionLineEdit::slotTextChanged(const QString& text)
     }
 }
 
-void ExpressionLineEdit::slotCompleteText(const QString& completionPrefix, bool isActivated)
+void ExpressionLineEdit::slotCompleteText(const QString& completionPrefix, ActivationMode mode)
 {
     int start, end;
     completer->getPrefixRange(start, end);
@@ -1030,7 +1030,7 @@ void ExpressionLineEdit::slotCompleteText(const QString& completionPrefix, bool
 
     // chain completions if we select an entry from the completer drop down
     // and that entry ends with '.' or '#'
-    if (isActivated) {
+    if (mode == ActivationMode::Activated) {
         std::string textToComplete = completionPrefix.toUtf8().constData();
         if (textToComplete.size()
             && (*textToComplete.crbegin() == '.' || *textToComplete.crbegin() == '#')) {
@@ -1042,12 +1042,12 @@ void ExpressionLineEdit::slotCompleteText(const QString& completionPrefix, bool
 
 void ExpressionLineEdit::slotCompleteTextHighlighted(const QString& completionPrefix)
 {
-    slotCompleteText(completionPrefix, false);
+    slotCompleteText(completionPrefix, ActivationMode::Highlighted);
 }
 
 void ExpressionLineEdit::slotCompleteTextSelected(const QString& completionPrefix)
 {
-    slotCompleteText(completionPrefix, true);
+    slotCompleteText(completionPrefix, ActivationMode::Activated);
 }
 
 
@@ -1116,13 +1116,13 @@ void ExpressionTextEdit::setDocumentObject(const App::DocumentObject* currentDoc
             completer,
             qOverload<const QString&>(&QCompleter::activated),
             this,
-            &ExpressionTextEdit::slotCompleteText
+            &ExpressionTextEdit::slotCompleteTextSelected
         );
         connect(
             completer,
             qOverload<const QString&>(&QCompleter::highlighted),
             this,
-            &ExpressionTextEdit::slotCompleteText
+            &ExpressionTextEdit::slotCompleteTextHighlighted
         );
         connect(this, &ExpressionTextEdit::textChanged2, completer, &ExpressionCompleter::slotUpdate);
         connect(
@@ -1155,7 +1155,7 @@ void ExpressionTextEdit::slotTextChanged()
     }
 }
 
-void ExpressionTextEdit::slotCompleteText(const QString& completionPrefix)
+void ExpressionTextEdit::slotCompleteText(const QString& completionPrefix, ActivationMode mode)
 {
     QTextCursor cursor = textCursor();
     int start, end;
@@ -1165,17 +1165,31 @@ void ExpressionTextEdit::slotCompleteText(const QString& completionPrefix)
         cursor.movePosition(QTextCursor::NextCharacter, QTextCursor::MoveAnchor, end - pos);
     }
     cursor.movePosition(QTextCursor::PreviousCharacter, QTextCursor::KeepAnchor, end - start);
+
     Base::FlagToggler<bool> flag(block, false);
     cursor.insertText(completionPrefix);
     completer->updatePrefixEnd(cursor.positionInBlock());
 
-    std::string textToComplete = completionPrefix.toUtf8().constData();
-    if (textToComplete.size()
-        && (*textToComplete.crbegin() == '.' || *textToComplete.crbegin() == '#')) {
-        completer->slotUpdate(cursor.block().text(), cursor.positionInBlock());
+    // chain completions only when activated (Enter/Click), not when highlighted (arrow keys)
+    if (mode == ActivationMode::Activated) {
+        std::string textToComplete = completionPrefix.toUtf8().constData();
+        if (!textToComplete.empty()
+            && (*textToComplete.crbegin() == '.' || *textToComplete.crbegin() == '#')) {
+            completer->slotUpdate(cursor.block().text(), cursor.positionInBlock());
+        }
     }
 }
 
+void ExpressionTextEdit::slotCompleteTextHighlighted(const QString& completionPrefix)
+{
+    slotCompleteText(completionPrefix, ActivationMode::Highlighted);
+}
+
+void ExpressionTextEdit::slotCompleteTextSelected(const QString& completionPrefix)
+{
+    slotCompleteText(completionPrefix, ActivationMode::Activated);
+}
+
 void ExpressionTextEdit::keyPressEvent(QKeyEvent* e)
 {
     Base::FlagToggler<bool> flag(block, true);
@@ -1208,9 +1222,8 @@ void ExpressionTextEdit::keyPressEvent(QKeyEvent* e)
                 if (!completer->popup()->currentIndex().isValid()) {
                     completer->popup()->setCurrentIndex(completer->popup()->model()->index(0, 0));
                 }
-                // insert completion
                 completer->setCurrentRow(completer->popup()->currentIndex().row());
-                slotCompleteText(completer->currentCompletion());
+                slotCompleteText(completer->currentCompletion(), ActivationMode::Highlighted);
 
                 // refresh completion list
                 completer->setCompletionPrefix(completer->currentCompletion());
diff --git a/src/Gui/ExpressionCompleter.h b/src/Gui/ExpressionCompleter.h
index 7db07b881e..3294aac78e 100644
--- a/src/Gui/ExpressionCompleter.h
+++ b/src/Gui/ExpressionCompleter.h
@@ -44,6 +44,12 @@ class ObjectIdentifier;
 namespace Gui
 {
 
+enum class ActivationMode
+{
+    Highlighted,  // browsing with arrow keys
+    Activated     // confirmed selection (Enter/Click)
+};
+
 class GuiExport ExpressionValidator: public QValidator
 {
     Q_OBJECT
@@ -123,8 +129,7 @@ Q_SIGNALS:
     void textChanged2(QString text, int pos);
 public Q_SLOTS:
     void slotTextChanged(const QString& text);
-    // activated == pressed enter on the completion item
-    void slotCompleteText(const QString& completionPrefix, bool isActivated);
+    void slotCompleteText(const QString& completionPrefix, ActivationMode mode);
     void slotCompleteTextHighlighted(const QString& completionPrefix);
     void slotCompleteTextSelected(const QString& completionPrefix);
 
@@ -159,7 +164,9 @@ Q_SIGNALS:
     void textChanged2(QString text, int pos);
 public Q_SLOTS:
     void slotTextChanged();
-    void slotCompleteText(const QString& completionPrefix);
+    void slotCompleteText(const QString& completionPrefix, ActivationMode mode);
+    void slotCompleteTextHighlighted(const QString& completionPrefix);
+    void slotCompleteTextSelected(const QString& completionPrefix);
     void adjustCompleterToCursor();
 
 private: