Apparently there has been a new addition to WordPress and I cannot figure out why it is throwing this error. I tried to look up the issue, but could not find anyone else having a problem!
The site has no plugins active right now and it is doing this will all themes I tested it on.
It only happens when I use the block editor, when I do a page with my ACF Pro fields it updates fine.
If I use the block editor and try to update the page to publish I get publishing failed and then this fatal error shows.
Does anyone have any ideas? Thanks for any leads on this!
Fatal error: Uncaught Error: Class “WP_HTML_Tag_Processor” not found in /nas/content/live/xxxxx/wp-includes/blocks/heading.php:27 Stack trace: #0 /nas/content/live/xxxx/wp-includes/class-wp-block.php(258): block_core_heading_render(Array, ‘\n<h1 class=”wp-…’, Object(WP_Block)) #1 /nas/content/live/xxxx/wp-includes/blocks.php(1051): WP_Block->render() #2 /nas/content/live/xxxxx/wp-includes/blocks.php(1089): render_block(Array) #3 /nas/content/live/xxxx/wp-includes/class-wp-hook.php(308): do_blocks(‘<!– wp:heading…’) #4 /nas/content/live/xxxx/wp-includes/plugin.php(205): WP_Hook->apply_filters(‘<!– wp:heading…’, Array) #5 /nas/content/live/xxxxx/wp-includes/rest-api/endpoints/class-wp-rest-posts-controller.php(1860): apply_filters(‘the_content’, ‘<!– wp:heading…’) #6 /nas/content/live/xxxxx/wp-includes/rest-api/endpoints/class-wp-rest-posts-controller.php(569): WP_REST_Posts_Controller->prepare_item_for_response(Object(WP_Post), Object(WP_REST_Request)) #7 /nas/content/live/xxxxx/wp-includes/rest-api/class-wp-rest-server.php(1181): WP_REST_Posts_Controller->get_item(Object(WP_REST_Request)) #8 /nas/content/live/xxxxx/wp-includes/rest-api/class-wp-rest-server.php(1028): WP_REST_Server->respond_to_request(Object(WP_REST_Request), ‘/wp/v2/pages/(?…’, Array, NULL) #9 /nas/content/live/xxxxx/wp-includes/rest-api.php(535): WP_REST_Server->dispatch(Object(WP_REST_Request)) #10 /nas/content/live/xxxxx/wp-includes/rest-api.php(2889): rest_do_request(Object(WP_REST_Request)) #11 [internal function]: rest_preload_api_request(Array, ‘/wp/v2/pages/23…’) #12 /nas/content/live/xxxxx/wp-includes/block-editor.php(634): array_reduce(Array, ‘rest_preload_ap…’, Array) #13 /nas/content/live/xxxxx/wp-admin/edit-form-blocks.php(77): block_editor_rest_api_preload(Array, Object(WP_Block_Editor_Context)) #14 /nas/content/live/xxxxx/wp-admin/post.php(187): require(‘/nas/content/li…’) #15 {main} thrown in /nas/content/live/xxxxx/wp-includes/blocks/heading.php on line 27