Merge pull request #60628 from KoBeWi/first_among_us

doc/classes/SceneTree.xml

@@ -91,6 +91,7 @@
 			<return type="Node" />
 			<argument index="0" name="group" type="StringName" />
 			<description>
+				Returns the first node in the specified group, or [code]null[/code] if the group is empty or does not exist.
 			</description>
 		</method>
 		<method name="get_frame" qualifiers="const">

scene/main/scene_tree.cpp

@@ -981,12 +981,12 @@ bool SceneTree::has_group(const StringName &p_identifier) const {
 Node *SceneTree::get_first_node_in_group(const StringName &p_group) {
 	Map<StringName, Group>::Element *E = group_map.find(p_group);
 	if (!E) {
-		return nullptr; //no group
+		return nullptr; // No group.
 	}
 
-	_update_group_order(E->get()); //update order just in case
+	_update_group_order(E->get()); // Update order just in case.
 
-	if (E->get().nodes.size() == 0) {
+	if (E->get().nodes.is_empty()) {
 		return nullptr;
 	}