wp-includes/block-supports/generated-classname.php:51Adds the generated classnames to the output.
$block_typeWP_Block_Typearrayfunction wp_apply_generated_classname_support( $block_type ) { $attributes = array(); $has_generated_classname_support = block_has_support( $block_type, 'className', true ); if ( $has_generated_classname_support ) { $block_classname = wp_get_block_default_classname( $block_type->name ); if ( $block_classname ) { $attributes['class'] = $block_classname; } } return $attributes;}Introduced in 5.6.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/block-supports/generated-classname.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.