	public function show_screen_options() {
		global $wp_meta_boxes;

		if ( is_bool( $this->_show_screen_options ) )
			return $this->_show_screen_options;

		$columns = get_column_headers( $this );

		$show_screen = ! empty( $wp_meta_boxes[ $this->id ] ) || $columns || $this->get_option( 'per_page' );

		switch ( $this->base ) {
			case 'widgets':
				$this->_screen_settings = '<p><a id="access-on" href="widgets.php?widgets-access=on">' . __('Enable accessibility mode') . '</a><a id="access-off" href="widgets.php?widgets-access=off">' . __('Disable accessibility mode') . "</a></p>\n";
				break;
			case 'post' :
				$expand = '<fieldset class="editor-expand hidden"><legend>' . __( 'Additional settings' ) . '</legend><label for="editor-expand-toggle">';
				$expand .= '<input type="checkbox" id="editor-expand-toggle"' . checked( get_user_setting( 'editor_expand', 'on' ), 'on', false ) . ' />';
				$expand .= __( 'Enable full-height editor and distraction-free functionality.' ) . '</label></fieldset>';
				$this->_screen_settings = $expand;
				break;
			default:
				$this->_screen_settings = '';
				break;
		}

		/**
		 * Filters the screen settings text displayed in the Screen Options tab.
		 *
		 * This filter is currently only used on the Widgets screen to enable
		 * accessibility mode.
		 *
		 * @since 3.0.0
		 *
		 * @param string    $screen_settings Screen settings.
		 * @param WP_Screen $this            WP_Screen object.
		 */
		$this->_screen_settings = apply_filters( 'screen_settings', $this->_screen_settings, $this );

		if ( $this->_screen_settings || $this->_options )
			$show_screen = true;

		/**
		 * Filters whether to show the Screen Options tab.
		 *
		 * @since 3.2.0
		 *
		 * @param bool      $show_screen Whether to show Screen Options tab.
		 *                               Default true.
		 * @param WP_Screen $this        Current WP_Screen instance.
		 */
		$this->_show_screen_options = apply_filters( 'screen_options_show_screen', $show_screen, $this );
		return $this->_show_screen_options;
	}
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