First thing to do to avoid loosing your post content is to preview it first because in doing so, you already have it saved on the draft, then you may  proceed to hitting the post button, if you get the same error response, then try to close the browser and reload the page and the post content from the draft, it will send, if you continue to see this repeated, i will advise that you either check your browser settings or you make use of another browser.


This is not a threat and you don't have to convince anyone here that you're a genuine user, just locate where the problem is coming from and then you're good.