Also: https://mbasic.facebook.com

The Facebook mobile web page has been going through so much churn lately, I feel like they are working to make it less desirable relative to the app. Disabling access to messages was one of the big ones, but they also regularly change how the sharing links work (to where you can or cannot share from a given action). One of the most recent and enjoyable changes is that the unread count badge on notifications updates in the background, but the actual notification drop down doesn't. You have to go to the notifications page (see all notifications) to see what the new notification actually is.

And can use firefox to access messenger.