I’d say this is supposed to be like that…
I think I’ve got the solution:
1) In the WordPress directory, go to wp-includes –> js –> tinymce.
2) Open the file called “tiny_mce.js” in any text editor where you can see lines in the code (like Dreamweaver).
3) Find line number 33. There change the code to this.isSafari = false
4) Try posting again! It should work…
The problem is in the browser you use. The main rule is never to use Safari when posting on WordPress.
This is because you’re using some browser that isn’t “supported” by WordPress. I guess you’re using Safari, because I have Safari and that’s the only browser where the problem appears.
So, I suggest you to use Firefox when posting on WordPress. That is very annoying thing to do, but for now I think it’s the only solution.