### Godot version

v4.0.beta.custom_build [13f0158]

### System information

Windows 10

### Issue description

When doing operations (`begin_complex_operation` and `end_complex_operation`) with multiple selections in TextEdit, some of these selections don't revert upon undo. This behavior is affects some of script editor's operations, like duplicate selection and delete lines.

### Steps to reproduce

Open script editor, make multiple selections. Keep in mind what you have selected. Do duplicate selection (ctrl+shift+D). Undo (ctrl+Z). Compare the result to what you remember.

### Minimal reproduction project

N/A
_scroll_down(delta, false);
		}
		h_scroll->set_value(h_scroll->get_value() + pan_gesture->get_delta().x * 100);
		if (v_scroll->get_value() != prev_v_scroll || h_scroll->get_value() != prev_h_scroll) {
			accept_event(); 
		}
		return;
	}
	Ref<InputEventMouseMotion> mm = p_gui_input;
	if (mm.is_valid()) {
		Vector2i mpos = mm->get_position();
		if (is_layout_rtl()) {
			mpos.x = get_size().x - mpos.x;
		}
		if (mm->get_button_mask().has_flag(MouseButtonMask::LEFT) && get_viewport()->gui_get_drag_data() == Variant()) { 
			_reset_caret_blink_timer();
			if (draw_minimap && !dragging_selection) {
				_update_minimap_drag();
			}
			if (!dragging_minimap) {
				switch (selecting_mode) {
					case SelectionMode::SELECTION_MODE_POINTER: {
						_update_selection_mode_pointer();
					} break;
					case SelectionMode::SELECTION_MODE_WORD: {
						_update_selection_mode_word();
					} break;
					case SelectionMode::SELECTION_MODE_LINE: {
						_update_selection_mode_line();
					} break;