### Godot version

master

### System information

Godot v4.2.beta (0ea75d77c) - Windows 10.0.22621 - Vulkan (Forward+) - dedicated NVIDIA GeForce RTX 2070 (NVIDIA; 31.0.15.3598) - Intel(R) Core(TM) i7-10750H CPU @ 2.60GHz (12 Threads)

### Issue description

When any of the Import, Filesystem, Node, or History docks are floating, changing an editor feature crashes the engine.
Changing any setting or selecting a different profile triggers it.

This is because `EditorNode::_feature_profile_changed` assumes the docks are in a `TabContainer`, and if they are floating they aren't in one.


### Steps to reproduce

Make any of these docks floating: Import, Filesystem, Node, or History
Open Editor Features (Editor -> Manage Editor Features...)
Make a profile (if you have none) or change a setting on the existing profile

### Minimal reproduction project

n/a
if (!bool(EDITOR_GET("interface/scene_tabs/restore_scenes_on_load"))) {
		return false;
	}
	Ref<ConfigFile> config;
	config.instantiate();
	Error err = config->load(EditorPaths::get_singleton()->get_project_settings_dir().path_join("editor_layout.cfg"));
	if (err != OK) {
		return false;
	}
	if (!config->has_section(EDITOR_NODE_CONFIG_SECTION) || !config->has_section_key(EDITOR_NODE_CONFIG_SECTION, "open_scenes")) {
		return false;
	}
	Array scenes = config->get_value(EDITOR_NODE_CONFIG_SECTION, "open_scenes");
	return !scenes.is_empty();
}
bool EditorNode::ensure_main_scene(bool p_from_native) {