I'm not sure whether you're still following the other thread on this, but since you're asking for suggestions: Thomas helped me determine that if you're private browsing in FF, that's when you get the "notifications not available on this browser" message. So if that can't be changed/fixed, I think the wording should at least be changed to reflect the reason, if possible. And if the reason is not immediately known in any individual case, I think there should be Help documentation to the effect that private browsing disables notifications.
Good question about what to do about 10 edits in a short period of time. Maybe there should be options for each kind of notification about whether to group them or not. I would not want individual notices for wiki edits by the same user, but I'd want them for photo uploads, for example.
Messages are the sole opinion of the author, especially the fishy ones.