WP Still Generating 150x150 Thumbnail Size Even After Un-Setting Small Size in Functions.php

Question

I am using following code to prevent WordPress from creating some un required image sizes for my theme and only upload the original size

add_filter( 'intermediate_image_sizes_advanced', 'prefix_remove_default_images' );
function prefix_remove_default_images( $sizes ) {
 unset( $sizes['small']); // 150px
 unset( $sizes['medium']); // 300px
 unset( $sizes['large']); // 1024px
 unset( $sizes['medium_large']); // 768px
 return $sizes;
}

The code is somehow working and I am able to upload the original size but as you can see WordPress still generating 150x150 size images

As you can see I explicitly added unset( $sizes['small']); to the code, but this is still happening! Can you please let me know what I am missing here?

Answer 1

That's because there is no image size called small in WordPress. It's possible your theme registered it but the thumbnail size WordPress uses internally at 150x150 is named thumbnail not small