As Chris to some notification problems I created two accounts on its site this is what I notice.
I did the test that you can see below with the same result
1. No email received, neither for Baloo, nor for TFL, moreover I am almost sure that when a friendship was finalized, the initiator received an email.
2. The red counter on the bell is well incremented but when I open the drawer there is nothing new for Baloo.
So I thought, let's do the same thing on my site, I created two new accounts and redo the same experience for exactly the same result.
Then I reproduced the experience on UNA test site
Same, zero email notifications for everything, except emails for account creation.
And also this counter problem which increases for the TFL account but without notifications in the drawer.
So I think there is a problem here.