$RAIN$_POST$_GET$_FILES
/modules/FileManager/src/FileManager.php:935, FileManager::sendDownloadHeader()
readfile(): Filename cannot be empty
/modules/FileManager/src/FileManager.php:437, FileManager::downloadFile()
/lib/rain/RModule.php:578, RModule::bindMethod()
/modules/FileManager/src/FileManager.php:52, FileManager::show()
/lib/rain/R.php:1752, R::run()
/index.php:146