Facebook notifications won't show up?

[Scream Queen]

I've noticed that Facebook won't show new notifications and new messages anymore, unless I would open another facebook on another tab. and if I send message to a friend through FB chat, they won't receive it unless I send the message through a reply from an inbox.
I'm using firefox and I've also tried switching to google chrome, but the problem is still the same.

[Thunderoustank394]

I had this last week... the notifications for that day never showed up to my email or my facebook ... but they started showing up the next day.. just a glitch

[Sailor...]

Click on notifications and click "see all notifications"
On the right corner, there is a bunch of stuff which you can choose if you want to receive those types of notifications (Likes, Wall, etc.). Check to make sure "Comments" are checked in the box. Maybe you unchecked it without realizing it one time, which would make you stop receiving those notifications.