There are times when users have reported that the app didn't function properly or they experienced glitches. If Facebook not loading properly, make sure the cache in your browser is cleared. Setting the correct date and time from your computer's settings menu will allow Facebook to handle your content without any problems. Therefore, if your computer is set with the incorrect date and time, it may disrupt Facebook's operation. Additionally, if your computer is using an older version of its browser, you may experience this issue. Older versions often contain bugs, and therefore it's very important that you use the most current version of the browser on your computer.
See also - facebook notifications not working