PHP warning on admin / config page

[dregad]

I'm getting the following PHP warning when displaying Admin / Configuration Settings.

PHP 7.4.30 DokuWiki Release 2022-07-31 "Igor" Site Export plugin version 2022-05-03

Warning: Declaration of renderer_plugin_siteexport_pdf::header($text, $level, $pos) should be compatible with Doku_Renderer_xhtml::header($text, $level, $pos, $returnonly = false) in .../lib/plugins/siteexport/renderer/pdf.php on line 88

1 | 0.0001 | 362496 | {main}(  ) | .../doku.php:0
2 | 0.0147 | 1067816 | act_dispatch(  ) | .../doku.php:126
3 | 0.0148 | 1067816 | dokuwiki\ActionRouter::getInstance( $reinit = TRUE ) | .../actions.php:16
4 | 0.0148 | 1067928 | dokuwiki\ActionRouter->__construct(  ) | .../ActionRouter.php:60
5 | 0.0148 | 1068304 | dokuwiki\ActionRouter->setupAction( $actionname = 'admin' ) | .../ActionRouter.php:48
6 | 0.0150 | 1070856 | dokuwiki\Action\Admin->preProcess(  ) | .../ActionRouter.php:83
7 | 0.0152 | 1075120 | admin_plugin_config->handle(  ) | .../Admin.php:33
8 | 0.0153 | 1075312 | dokuwiki\plugin\config\core\Configuration->__construct(  ) | .../admin.php:40
9 | 0.0227 | 1130920 | dokuwiki\plugin\config\core\Configuration->initSettings(  ) | .../Configuration.php:56
10 | 0.0259 | 1227288 | dokuwiki\plugin\config\core\Setting\SettingRenderer->initialize( $default = 'xhtml', $local = NULL, $protected = NULL ) | .../Configuration.php:170
11 | 0.0263 | 1319512 | plugin_load( $type = 'renderer', $name = 'siteexport_pdf', $new = ???, $disabled = ??? ) | .../SettingRenderer.php:22
12 | 0.0263 | 1319512 | dokuwiki\Extension\PluginController->load( $type = 'renderer', $name = 'siteexport_pdf', $new = FALSE, $disabled = FALSE ) | .../pluginutils.php:54
13 | 0.0263 | 1319608 | class_exists( $classname = 'renderer_plugin_siteexport_pdf', $autoload = TRUE ) | .../PluginController.php:107
14 | 0.0263 | 1319688 | spl_autoload_call( $class_name = 'renderer_plugin_siteexport_pdf' ) | .../PluginController.php:107
15 | 0.0263 | 1319728 | load_autoload( $name = 'renderer_plugin_siteexport_pdf' ) | .../PluginController.php:107