PHP 7.4 Warning: implode(): Invalid arguments passed in \fpdm\fpdm->get_buffer()

[nbao]

i got some warning php in fpdm.php line 550
$buffer=implode("\n",$this->pdf_entries);
sometime $this->pdf_entries is null it is not array
suggestion $buffer=implode("\n",!empty($this->pdf_entries) ? $this->pdf_entries : []);

another warning php in fpdm.php line 1627
Warning: count(): Parameter must be an array or an object that implements Countable in \fpdm\fpdm->parsePDFEntries()
$CountLines = count($entries);
i suggest $CountLines = !empty($entries) ? count($entries) : 0;