Blesta 5.9.0 - Client's cannot open tickets fix

[Paul]

If you're running 5.9.0, clients may not be able to open tickets while authenticated. A simple solution, pending an official patch release is:

Edit /app/models/blacklist.php around line 255.

Look for:

public function verify(string $input, string $type)

Replace with:

public function verify(?string $input, string $type)