Glad to see that this is a known issue.
The Classic Editor plugin solution does not work for me. When I add
add_filter( ‘jetpack_allow_per_post_subscriptions’, ‘__return_true’ );
to the theme’s functions.php file the code shows within the dashboard center frame and other parts when navigation admin. Classic editor also does not work then, so I’m never able to see the checkbox per the classic editor. Not sure if it’s working for others but it is not for me.
I have to remove the code from the functions.php to use WP properly. It looks like the issue has been known since Dec 7, 2018, so hope to see a fix shortly.
