Merge pull request #96569 from AThousandShips/fix_tree_button

[Editor] Prevent duplicate `Open in Editor` buttons in scene tree dock

editor/gui/scene_tree_editor.cpp

@@ -516,10 +516,14 @@ void SceneTreeEditor::_update_node_tooltip(Node *p_node, TreeItem *p_item) {
 	String tooltip = p_node->get_name();
 
 	if (p_node == get_scene_node() && p_node->get_scene_inherited_state().is_valid()) {
-		p_item->add_button(0, get_editor_theme_icon(SNAME("InstanceOptions")), BUTTON_SUBSCENE, false, TTR("Open in Editor"));
+		if (p_item->get_button_by_id(0, BUTTON_SUBSCENE) == -1) {
+			p_item->add_button(0, get_editor_theme_icon(SNAME("InstanceOptions")), BUTTON_SUBSCENE, false, TTR("Open in Editor"));
+		}
 		tooltip += String("\n" + TTR("Inherits:") + " " + p_node->get_scene_inherited_state()->get_path());
 	} else if (p_node != get_scene_node() && !p_node->get_scene_file_path().is_empty() && can_open_instance) {
-		p_item->add_button(0, get_editor_theme_icon(SNAME("InstanceOptions")), BUTTON_SUBSCENE, false, TTR("Open in Editor"));
+		if (p_item->get_button_by_id(0, BUTTON_SUBSCENE) == -1) {
+			p_item->add_button(0, get_editor_theme_icon(SNAME("InstanceOptions")), BUTTON_SUBSCENE, false, TTR("Open in Editor"));
+		}
 		tooltip += String("\n" + TTR("Instance:") + " " + p_node->get_scene_file_path());
 	}