We have a wordpress installation on provider wpengine. When we try to update some plugins we get the fatal PHP error in subject. The provider support do not know how to help us. This is the call stack of the error:

"PHP Fatal error: Uncaught Error: Call to undefined function trailingslashit() in /nas/content/live/sillaindustrie/wp-includes/class-wp-textdomain-registry.php:103\nStack trace:\n#0 /nas/content/live/sillaindustrie/wp-includes/l10n.php(784): WP_Textdomain_Registry->set('default', 'it_IT', '/nas/content/li...')\n#1 /nas/content/live/sillaindustrie/wp-includes/load.php(1401): load_textdomain('default', '/nas/content/li...', 'it_IT')\n#2 /nas/content/live/sillaindustrie/wp-includes/load.php(278): wp_load_translations_early()\n#3 /nas/content/live/sillaindustrie/wp-settings.php(74): wp_maintenance()\n#4 /nas/content/live/sillaindustrie/wp-config.php(67): require_once('/nas/content/li...')\n#5 /nas/content/live/sillaindustrie/wp-load.php(50): require_once('/nas/content/li...')\n#6 /nas/content/live/sillaindustrie/wp-blog-header.php(13): require_once('/nas/content/li...')\n#7 /nas/content/live/sillaindustrie/index.php(17): require('/nas/content/li...')\n#8 {main}\n thrown in /nas/content/live/sillaindustrie/wp-includes/class-wp-textdomain-registry.php on line 103, referer: https://silla.industries/wp-admin/update-core.php?action=do-plugin-upgrade"

It seems to be related to WPML plugin or similar, any suggest? Thanks G.

I tried to update wordpress plugin, but I cannot understand the source of the error. Maybe it is plugins incompatibility but I don't know how to discover it.

CodePudding user response：

Check you have installed php-psr. I had this error as I hadn't installed php8.1-psr

CodePudding user response：

Looks like the formatting.php functions are not available anymore when updating.