- Create custom function (randomString()) for generating cryptographically (and URL) safe strings.

- Replace usages of keygen and bin2hex(random_bytes()) with this function.

users.php

@@ -170,7 +170,7 @@ $num_rows = mysqli_fetch_row(mysqli_query($mysqli, "SELECT FOUND_ROWS()"));
     </div>
     <script>
         function generatePassword() {
-            document.getElementById("password").value = "<?php echo keygen() ?>"
+            document.getElementById("password").value = "<?php echo randomString() ?>"
         }
     </script>