Attributes Filter doesn’t work

To allow some attributes I addes this code to my functions.php

—————-
add_filter( ‘svg_allowed_attributes’, function ( $attributes ) {

// Do what you want here…

// This should return an array so add your attributes to
// to the $attributes array before returning it. E.G.

$attributes[] = ‘vector-effect’;

return $attributes;
} );
—————-

I added the vector-effect attribute to a svg-File but after the upload the attribute is removed from the svg-file. Where do i make a mistake? Thanks!