DirectorySlash Off

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RewriteRule ^/?@([a-z0-9]([._](?![._])|[a-z0-9]){2,30}[a-z0-9])$ /index.php?_action=lookupuser&handle=$1 [L]

RewriteRule ^/?vendor/ - [F,L]
RewriteRule ^/?composer\. - [F,L]