Undefined index on 404 page

[freakimkaefig]

The plugin produces errors on the 404 page:
Notice: Undefined index: in /some/path/pico/plugins/PicoPlacing/PicoPlacing.php on line 134
Notice: Undefined index: in /some/path/pico/plugins/PicoPlacing/PicoPlacing.php on line 135

Can be hotfixed by checking for $currentPage in onPagesLoaded:

if ( isset( $currentPage ) ) {
    $curr = $currentPage['placing'];
    
    $keys = array_keys($sorted_pages);
    $keyIndexes = array_flip( $keys );
    
    $prev = ( isset( $keys[ $keyIndexes[ $curr ] - 1 ] ) ) ? $prev = $keys[ $keyIndexes[ $curr ] - 1 ] : FALSE;
    $next = ( isset( $keys[ $keyIndexes[ $curr ] + 1 ] ) ) ? $next = $keys[ $keyIndexes[ $curr ] + 1 ] : FALSE;
    
    $nextPage = ( $next ) ? $sorted_pages[$next] : null;
    $previousPage = ( $prev ) ? $sorted_pages[$prev] : null;
}