Hmm... There was no new update for Firefox until today (The version that I used four days ago when the problem was encountered was v.59.03. The latest version which I'm using since today is v.60.0). I just logged out, started IE 11 (v.11.0.9600.19002), logged back into the site, went into PM and tried to reply to my friend's PM and still saw only blank text in the reply message's body. That's very strange that both Firefox and IE are exhibiting the same problem. I sent you a test PM. Please see if you experience the same problem after you hit the "Reply" button (You can try it with Chrome, Opera,
KMeleon or whatever browser you use so that you can possibly see the problem for yourself). IMHO, if the problem is being encountered in more than one browser, then chances are more likely that the problem is not on the client side - I'm not doubting you when you say that the problem is not on the server side. Was a vBulletin add-on or update patch recently installed?