I'm getting blank email notifications. When I click on them, they don't load. But when I go the long way through my profile stream, those comments appear. The blank ones are comments on an Immersion Tier level up.
Just got a notification that I have reached a new tier. Waiting to see if any blank emails arrive. I'll get back to you in the next few days.
I've been told, sorry but I don't remember by whom, that those blank emails are from comments about your new tier. It's good to have that verified and to know there is a way to have a look at the message. Today I also noticed for the first time that under some comments there is a number next to the "like" option and clicking it will bring up the names of some, though not all, of those whose chose "like".
EranuUvavu has just posted on my stream that he received a similar blank email notification which coincided with his reaching a higher tier. He said I could bring it to your attention.