It is a browser issue. Some browsers do it worse than others. Try another browser, or click more options.
Ok. Never actually used that more options button. Thanks. Might see if Java works in google chrome now.
I started having that problem last year and never figured out why. I found that if I unchecked "Use the rich text editor to create and edit messages" in my Preferences I can edit all I want. The problem then became how to format what I posted. I have adapted by learning some of the formatting as needed like how to Bold and so forth.
I use three computers with a different browser on each. Chrome, IE, or Firefox does not matter, for me at least. I don't know if it was a Java update or something else. I've gotten used to it although it is a hassle sometimes, I edit much more often than I use formatting so I've not bothered dig into it to understand what broke. Maybe when I have more time I'll have to see why mine hasn't been working. Or possibly it is and I don't know it My post was mainly to let you know that you could get back to editing relatively easily if you were willing to give up the formatting controls. Here's my edit screen:
Usually when that happens to me I just press "More Option." It sends to different page but I can still edit my message.