added webrtc, pre-4.3 update to fix cyclic dependency

main_menu.tscn

@@ -0,0 +1,26 @@
+[gd_scene load_steps=2 format=3 uid="uid://dogu37xma5vsp"]
+
+[ext_resource type="Script" path="res://main_menu.gd" id="1_q3q3u"]
+
+[node name="MainMenu" type="Control"]
+layout_mode = 3
+anchors_preset = 15
+anchor_right = 1.0
+anchor_bottom = 1.0
+grow_horizontal = 2
+grow_vertical = 2
+script = ExtResource("1_q3q3u")
+
+[node name="Button" type="Button" parent="."]
+layout_mode = 0
+offset_right = 8.0
+offset_bottom = 8.0
+text = "Test WebRTC"
+
+[node name="HBoxContainer" type="HBoxContainer" parent="."]
+layout_mode = 0
+offset_top = 56.0
+offset_right = 40.0
+offset_bottom = 96.0
+
+[connection signal="pressed" from="Button" to="." method="_on_button_pressed"]