Error and fix suggestion “explode() expects parameter 2 to be string…”

I’ve got the error:

Warning: explode() expects parameter 2 to be string, array given in C:\xampp\...\wp-content\plugins\wp-gallery-custom-links\wp-gallery-custom-links.php on line 205

Warning: array_merge(): Argument #2 is not an array in C:\xampp\...\wp-content\plugins\wp-gallery-custom-links\wp-gallery-custom-links.php on line 205

Warning: explode() expects parameter 2 to be string, array given in C:\xampp\...\wp-content\plugins\wp-gallery-custom-links\wp-gallery-custom-links.php on line 216

Warning: array_merge(): Argument #1 is not an array in C:\xampp\...\wp-content\plugins\wp-gallery-custom-links\wp-gallery-custom-links.php on line 216

Warning: array_unique() expects parameter 1 to be array, null given in C:\xampp\...\wp-content\plugins\wp-gallery-custom-links\wp-gallery-custom-links.php on line 220

Warning: Invalid argument supplied for foreach() in C:\xampp\...\wp-content\plugins\wp-gallery-custom-links\wp-gallery-custom-links.php on line 222

The fastest way I’ve found to fix it is changing the line 205 and 216 to:

if ( is_array( $attr['ids'] ) ) {
  $attachment_ids = array_merge( $attachment_ids, $attr['ids'] );
} else {
  $attachment_ids = array_merge( $attachment_ids, explode( ',', $attr['ids'] ) );
}

if ( is_array( $attr['include'] ) ) {
  $attachment_ids = array_merge( $attachment_ids, $attr['include'] );
} else {
  $attachment_ids = array_merge( $attachment_ids, explode( ',', $attr['include'] ) );
}