If I'm not logged in, don't show me a live "Save" button at the bottom

I created a thread. Later, I went to the thread and didn't realize that I had logged out (or been logged out). I typed three paragraphs and clicked the Save button. THEN I was informed that I was "not authorized to post."

Tried to go back. Everything I wrote was gone. So I had to re-type the whole g- d- thing.

Instead of giving people who aren't logged in a live Save button, which gives us the misleading impression that we can post, you should instead gray out the Save button and indicate --- before we lose everything we typed --- that we need to sign in. Or have a "You must login" button. Or stop us from typing to begin with. Fill the box with "You must login." Dozens of options.