If you have been having problems accessing Facebook features such as messages and are using Firefox (Mozilla) as a browser, there is a fix. Apparently, Facebook requires that you input them as being able to keep their cookies forever. You need to go into the “Tools>Options” on the menu bar for Firefox and select “Privacy.”
After you have opened the “Privacy” option, you will see a line that says “Accept Cookies from Sites.” Check that box.
To the right of that line is an icon labeled, “Exceptions.” Open that.
Type in the two following exceptions: http://www.facebook.com and https://facebook.com
“Allow” each of these and they will show up in the box immediately underneath.
If you are like me, always paranoid about malicious cookies, you can still check “ask every time” in the “keep until” drop menu.
This should get rid of your problems with messages and other features. Leave it up to the Zuck for trying to screw us up again.