### Godot version

4.0.dev(2fdaf2919c03ab50f971f2d51616d4ee329d29af)

### System information

any

### Issue description

AnimationPlayer is unintentionally hidden.

https://user-images.githubusercontent.com/61938263/217088704-c1ad44d6-ef7b-4b10-b351-f9f9fa166e39.mp4


### Steps to reproduce

Select AnimationTree -> Select AnimationPlayer

### Minimal reproduction project

N/A
dock_float->set_text(TTR("Make Floating"));
	dock_float->set_focus_mode(Control::FOCUS_NONE);
	dock_float->set_h_size_flags(Control::SIZE_SHRINK_CENTER);
	dock_float->connect("pressed", callable_mp(this, &EditorNode::_dock_make_float));
	dock_vb->add_child(dock_float);
	dock_select_popup->reset_size();
	for (int i = 0; i < DOCK_SLOT_MAX; i++) {
		dock_slot[i]->set_custom_minimum_size(Size2(170, 0) * EDSCALE);
		dock_slot[i]->set_v_size_flags(Control::SIZE_EXPAND_FILL);
		dock_slot[i]->set_popup(dock_select_popup);
		dock_slot[i]->connect("pre_popup_pressed", callable_mp(this, &EditorNode::_dock_pre_popup).bind(i));
		dock_slot[i]->set_drag_to_rearrange_enabled(true);
		dock_slot[i]->set_tabs_rearrange_group(1);
		dock_slot[i]->connect("tab_changed", callable_mp(this, &EditorNode::_dock_tab_changed));
		dock_slot[i]->set_use_hidden_tabs_for_min_size(true);
	}
	dock_drag_timer = memnew(Timer);
	add_child(dock_drag_timer);
	dock_drag_timer->set_wait_time(0.5);
	dock_drag_timer->set_one_shot(true);
	dock_drag_timer->connect("timeout", callable_mp(this, &EditorNode::_save_docks));
	top_split = memnew(VSplitContainer);
	center_split->add_child(top_split);
	top_split->set_v_size_flags(Control::SIZE_EXPAND_FILL);
	top_split->set_collapsed(true);
	VBoxContainer *srt = memnew(VBoxContainer);
	srt->set_v_size_flags(Control::SIZE_EXPAND_FILL);
	top_split->add_child(srt);
	srt->add_theme_constant_override("separation", 0);
	tab_preview_panel = memnew(Panel);