wp-includes/class-wp-theme-json.php:884Enables some opt-in settings if theme declared support.
$theme_jsonarrayarray protected static function maybe_opt_in_into_settings( $theme_json ) { $new_theme_json = $theme_json; if ( isset( $new_theme_json['settings']['appearanceTools'] ) && true === $new_theme_json['settings']['appearanceTools'] ) { static::do_opt_in_into_settings( $new_theme_json['settings'] ); } if ( isset( $new_theme_json['settings']['blocks'] ) && is_array( $new_theme_json['settings']['blocks'] ) ) { foreach ( $new_theme_json['settings']['blocks'] as &$block ) { if ( isset( $block['appearanceTools'] ) && ( true === $block['appearanceTools'] ) ) { static::do_opt_in_into_settings( $block ); } } } return $new_theme_json; }Introduced in 5.9.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/class-wp-theme-json.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.