Fatal error: Uncaught TypeError: Argument 1 passed to WordPress\Plugin\Encyclopedia\Content_Filter::addCrossLinks() must be of the type string, null given, called in /www/htdocs/w0146a33/innovativeit.de/wp-includes/class-wp-hook.php on line 287 and defined in /www/htdocs/w0146a33/innovativeit.de/wp-content/plugins/encyclopedia-lexicon-glossary-wiki-dictionary/classes/content-filter.php:53 Stack trace: #0 /www/htdocs/w0146a33/innovativeit.de/wp-includes/class-wp-hook.php(287): WordPress\Plugin\Encyclopedia\Content_Filter::addCrossLinks(NULL) #1 /www/htdocs/w0146a33/innovativeit.de/wp-includes/plugin.php(206): WP_Hook->apply_filters(NULL, Array) #2 /www/htdocs/w0146a33/innovativeit.de/wp-includes/formatting.php(3823): apply_filters('the_content', '') #3 /www/htdocs/w0146a33/innovativeit.de/wp-includes/class-wp-hook.php(287): wp_trim_excerpt('', Object(WP_Post)) #4 /www/htdocs/w0146a33/innovativeit.de/wp-includes/plugin.php(206): WP_Hook->apply_filters('', Array) #5 /www/htdocs/w0146a33/innovativeit.de/wp-includes/post-templ in /www/htdocs/w0146a33/innovativeit.de/wp-content/plugins/encyclopedia-lexicon-glossary-wiki-dictionary/classes/content-filter.php on line 53