Fatal error: Uncaught Exception: Unable to open file /var/www/html/extensions/DownloadBook/extension.json: filemtime(): stat failed for /var/www/html/extensions/DownloadBook/extension.json in /var/www/html/includes/registration/ExtensionRegistry.php:182
Stack trace:
#0 /var/www/html/includes/GlobalFunctions.php(52): ExtensionRegistry->queue()
#1 /var/www/html/LocalSettings.php(315): wfLoadExtension()
#2 /var/www/html/includes/Setup.php(204): require_once('...')
#3 /var/www/html/includes/WebStart.php(93): require_once('...')
#4 /var/www/html/index.php(44): require('...')
#5 {main}
thrown in /var/www/html/includes/registration/ExtensionRegistry.php on line 182