Facebook push notifications not working in OSX

I've tried several times to get my Facebook account added through System Prefs' Internet Accounts. I can set it up okay, calendars are working, and FB posting works from the Notification Center and Safari.

But... Push notifications for new messages aren't working.

I have a 3-computer system (3 MacBooks) with iCloud Keychain. Sometimes, when I try to turn on the Facebook account, I get notifications on one of the three computer, sometimes none, never more than one.

I've also played around with adding a 2nd FB account (and disabling the 1st) on some of the 3 computers. Again, no consistency with the notifications. It feels like I have a corrupted plist or cache somewhere.

I know that push is working from FB, since I get notifications on my iPhone every time.

The only hint I've found is through Console (messages not consecutive, shown at the end of the post).

Any suggestions? Any hidden cache files to delete?

Thanks in advance!

14-05-20 08:49:26,868 com.apple.facebook.xpc[1820]: /SourceCache/Social/Social-279.11/Facebook/FacebookXPCService/FBDSession.m - -[FBDSession revokeAllAccessTokensForDeviceWithCompletion:] - 336 - No master token to sign the invalidation request!

14-05-20 10:14:13,603 SocialPushAgent[817]: ApplePushService: APSConnection being used without a delegate queue

14-05-21 07:43:29,430 SocialPushAgent[817]: __45-[SPAFacebookService unregisterAccount:uuid:]_block_invoke [219] -- *** responseCode: 400. POST of destroy UUID=12345ABC-AB88-3ABC-4CDE-5FGHIJKLMNOP for account <my FB account> failed. Error: (null).

Response: {"error":{"message":"(#100) Invalid device_uuid","type":"OAuthException","code":100}}

14-05-21 07:55:36,070 SocialPushAgent[817]: __45-[SPAFacebookService unregisterAccount:uuid:]_block_invoke [219] -- *** responseCode: 400. POST of destroy UUID=12345ABC-AB88-3ABC-4CDE-5FGHIJKLMNOP for account <my FB account> failed. Error: (null).

Response: {"error":{"message":"The access token was invalidated on the device.","type":"OAuthException","code":190}}