id summary reporter owner description type status priority milestone component version severity resolution keywords cc focuses 46375 WordPress discovery MIME type killua99 "Some plugins, like WooCommerce are having problems when trying to upload a CSV file. Seems to be an issue in the PHP Library itself or not I'm 100 % clear yet. In my case on Pantheon server I've this issue with WordPress 5.1 and WooCommerce 3.5.5 Good description about it is in this comment https://wordpress.org/support/topic/wp-5-0-1-breaks-woocommerce-csv-import/page/2/#post-11234845 where @tgglv point out that the PHP Library finfo_open seems to act different. And perhaps the use of /usr/share/misc/magic should improve that finfo. The function affected is https://github.com/WordPress/WordPress/blob/master/wp-includes/functions.php#L2558 Something like this library: https://svn.apache.org/repos/asf/httpd/httpd/trunk/docs/conf/mime.types Could help to figure the mime. This php component use it. https://github.com/ralouphie/mimey Trace issues: https://core.trac.wordpress.org/ticket/45615 https://github.com/woocommerce/woocommerce/issues/22208 /cc @dougaitken " defect (bug) closed normal Upload normal duplicate