Hi @furion, Thank you very much for providing the SteemData Notify service.

I had already explained the reasons for the different memo lengths in this article, Thank you again for the clarification.

As for Bug,

    settings = db.settings.find_one({'_id': _id})
    if settings:
        db.settings.update_one(
            {'_id': _id, 'username': op['from']},
            {'$set': {'confirmed': True}}
        )

I think it would be better to change above code to:

    settings = db.settings.find_one({'_id': _id, 'username': op['from']})
    if settings:
        db.settings.update_one(
            {'_id': _id, 'username': op['from']},
            {'$set': {'confirmed': True}}
        )

Otherwise, It may cause minor problems in some extreme cases .
I'll submit this issues on Github when I finished the study of your great code.