Adding ad density to meta property

Is it possible to give fb:use_automatic_ad_placement the value of enable=true ad_density=default/medium/low ( https://developers.facebook.com/docs/instant-articles/monetization/ad-placement#ad-density )?

When I do ...->addMetaProperty( 'fb:use_automatic_ad_placement', 'enable=true ad_density=default' ); the plugin would change it to back to content=true Is it possible to change the value of that particular field?