Core system fast 404 doesn’t display when page not found

In Drupal 8.7 After uncommented the lines in settings.php for display a fast 404. $config[‘system.performance’][‘fast_404’][‘exclude_paths’] = ‘/\/(?:styles)|(?:system\/files)\//’;$config[‘system.performance’][‘fast_404’][‘paths’] = ‘/\.(?:txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i’;$config[‘system.performance’][‘fast_404’][‘html’] = ‘<!DOCTYPE html><html><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL “@path” was not found on this server.</p></body></html>’; I can not make it working .. I always get the standard 404 page not found. Any idea ?

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linux mint app installation

i cant install anything on my mint linux and this is this is the terminals answer dpkg: error processing package atom (–install): dependency problems – leaving unconfigured Processing triggers for gnome-menus (3.13.3-11ubuntu1.1) … Processing triggers for desktop-file-utils (0.23+linuxmint6) … Processing triggers for mime-support (3.60ubuntu1) … Errors were encountered while processing: atom

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