Half bug concealing this, something had escaped me, it seems that a delay of 120 seconds was introduced in the options of notifications, according to my tests, it is the cause of several problems including this one.
The goal is to clean email notifications IF they have been delivered to the site or by push. So it is normal that we do not receive emails because we are online.
However, we should have it on the site. I also have problems with empty email notifications from b1, it's also linked. (relieved) Temporary solution for all the problems that concern the notifications, is to indicate a delay = to Zero, then everything seems to work as before, including the simple votes (thumb).