Trying to get property ‘comment_approved’ of non-object

I log a lot of Exeptions right after a user submits a new comment:

Notice: Trying to get property ‘comment_approved’ of non-object

plugins/subscribe-to-comments-reloaded/wp_subscribe_reloaded.php in stcr\wp_subscribe_reloaded::comment_content_prepend at line 1668

It seems that $comment->comment_approved is not set right after the comment has been submitted.

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