I love regex problems:

if ($filename =~ /(.*)\.(.*)?/ig)
{    my $fname = $1;
    my $ext = $2;
        
    $fname =~ s/\W/_/g;
    $filename = $fname . '.' . $ext;
}
else
{    $filename =~ s/\W/_/g;
}
[download]

The only case I could find where it breaks is when you have a filename containing a dot (.) without an extension, but I don't know if that's a real case or not.

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Washizu
Acoustic Rock