"Why didn't you reply to me messages? Didn't you see the notification? You rude son of a -"
As a friend of mine reminded me last month, Facebook filters your messages all the time, so you may not get a notification. It may not be that obvious to you. Go to the messages pane and you'll see the headings for Inbox and Other.
Didn't realise you even had 'Other'?
"Your messages get filtered automatically so you mostly see stuff from friends and people you may know in your inbox."
The keyword is 'mostly.' As in "they mostly come at night. Mostly." (Aliens, 1986)
What is the "Other" folder in my messages?
Facebook helpfully provides the definition in its' help pages:
Your Other folder is where you'll find messages and emails that have been filtered out of your inbox. You can change your filter preference right from your inbox.
To get to your Other folder, go to Messages on the left side of the homepage. At the top left of your main messages view, click Other.
On the right of the messaging page, you also have a More menu which further changes the filter view for Unread, Archived and Spam.
To review your filtering options, click Other > Edit Preferences. These filters replace the old "Who can send you Facebook messages" setting.
What's the difference between Basic and Strict Filtering? Basic Filtering mostly shows messages from friends and people you may know (note 'may' know) in your inbox. Typically, messages from other people will go to your Other folder, and you won't receive a notification about them.
Choose Strict Filtering and you'll see mostly messages from friends in your inbox. Some messages from people you want to hear from may go to your Other folder.
Whichever filter you choose, you may sometimes get messages in your inbox from people you're not connected to and some messages from people you know may go to Other. Great, isn't it?
So: not reliable and no warranty provided.
Facebook gives some examples of when unwanted messages may go to your inbox:
- A friend of a friend includes you in a message along with some of your mutual friends
- A member of a group you're in messages you or includes you in a message
- A friend who isn't on Facebook uses your contact info to send you a message from the Facebook Messenger app
Commerce over-rides all. RC