diff --git a/radio/src/thirdparty/libopenui/src/CMakeLists.txt b/radio/src/thirdparty/libopenui/src/CMakeLists.txt
index 3fc35eb0e..788521440 100644
--- a/radio/src/thirdparty/libopenui/src/CMakeLists.txt
+++ b/radio/src/thirdparty/libopenui/src/CMakeLists.txt
@@ -32,6 +32,7 @@ set(LIBOPENUI_SRC
   table.cpp
   modal_window.cpp
   dialog.cpp
+  expansion_panel.cpp
   )
 
 if(SOFTWARE_KEYBOARD)
diff --git a/radio/src/thirdparty/libopenui/src/expansion_panel.cpp b/radio/src/thirdparty/libopenui/src/expansion_panel.cpp
new file mode 100644
index 000000000..a775a91f8
--- /dev/null
+++ b/radio/src/thirdparty/libopenui/src/expansion_panel.cpp
@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) OpenTX
+ *
+ * Source:
+ *  https://github.com/opentx/libopenui
+ *
+ * This file is a part of libopenui library.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ */
+
+#include "expansion_panel.h"
+
+ExpansionPanelHeader::ExpansionPanelHeader(ExpansionPanel * parent):
+  FormGroup(parent, {0, 0, parent->width(), parent->height()}, FORWARD_SCROLL)
+{
+}
+
+bool ExpansionPanelHeader::onTouchEnd(coord_t, coord_t)
+{
+  static_cast<ExpansionPanel *>(parent)->toggle();
+  setFocus();
+  return true;
+}
+
+void ExpansionPanelHeader::onEvent(event_t event)
+{
+  auto panel = static_cast<ExpansionPanel *>(parent);
+
+  if (event == EVT_KEY_BREAK(KEY_ENTER)) {
+    panel->toggle();
+  }
+  else if (event == EVT_ROTARY_RIGHT && !panel->isOpen) {
+    panel->getNextField()->setFocus(SET_FOCUS_FORWARD);
+  }
+  else {
+    FormGroup::onEvent(event);
+  }
+}
diff --git a/radio/src/thirdparty/libopenui/src/expansion_panel.h b/radio/src/thirdparty/libopenui/src/expansion_panel.h
index b624996c7..08fbb9126 100644
--- a/radio/src/thirdparty/libopenui/src/expansion_panel.h
+++ b/radio/src/thirdparty/libopenui/src/expansion_panel.h
@@ -78,31 +78,4 @@ class ExpansionPanel: public FormGroup {
     bool isOpen = false;
 };
 
-ExpansionPanelHeader::ExpansionPanelHeader(ExpansionPanel * parent):
-  FormGroup(parent, {0, 0, parent->width(), parent->height()}, FORWARD_SCROLL)
-{
-}
-
-bool ExpansionPanelHeader::onTouchEnd(coord_t, coord_t)
-{
-  static_cast<ExpansionPanel *>(parent)->toggle();
-  setFocus();
-  return true;
-}
-
-void ExpansionPanelHeader::onEvent(event_t event)
-{
-  auto panel = static_cast<ExpansionPanel *>(parent);
-
-  if (event == EVT_KEY_BREAK(KEY_ENTER)) {
-    panel->toggle();
-  }
-  else if (event == EVT_ROTARY_RIGHT && !panel->isOpen) {
-    panel->getNextField()->setFocus(SET_FOCUS_FORWARD);
-  }
-  else {
-    FormGroup::onEvent(event);
-  }
-}
-
 #endif // _EXPANSION_PANEL_H_