Minor "Merge From Scene" improvements

editor/editor_sub_scene.cpp

@@ -73,8 +73,8 @@ void EditorSubScene::_notification(int p_what) {
 
 	if (p_what == NOTIFICATION_VISIBILITY_CHANGED) {
 
-		if (!is_visible_in_tree()) {
-		}
+		if (is_visible() && scene == NULL)
+			_path_browse();
 	}
 }
 
@@ -232,7 +232,7 @@ EditorSubScene::EditorSubScene() {
 	hb->add_child(path);
 	path->set_h_size_flags(SIZE_EXPAND_FILL);
 	Button *b = memnew(Button);
-	b->set_text(" .. ");
+	b->set_text(TTR("Browse"));
 	hb->add_child(b);
 	b->connect("pressed", this, "_path_browse");
 	vb->add_margin_child(TTR("Scene Path:"), hb);

editor/scene_tree_dock.cpp

@@ -1942,7 +1942,13 @@ void SceneTreeDock::set_selected(Node *p_node, bool p_emit_selected) {
 
 void SceneTreeDock::import_subscene() {
 
-	import_subscene_dialog->popup_centered_ratio();
+	Size2 popup_size = Size2(500, 800) * editor_get_scale();
+	Size2 window_size = get_viewport_rect().size;
+
+	popup_size.x = MIN(window_size.x * 0.8, popup_size.x);
+	popup_size.y = MIN(window_size.y * 0.8, popup_size.y);
+
+	import_subscene_dialog->popup_centered(popup_size);
 }
 
 void SceneTreeDock::_import_subscene() {