Pressing Save in Blogger doesn't mean it did

You are have been writing the post on and off for the past few hours. You have been diligently pressing save to make sure you didn't lose your magnus opus. Other tabs are opened to access other websites for reference. Before switching between them, you still press save, just in case. Finally, after reading and correcting the post, you are finally satisfied with it. A final press of Save should do it. Then you hit Close.
The dialog box pops up and warns you that unsaved changes will be lost. You press Save again and hit Close. Blogger warns again. "But I just saved! What else do you want me to do?" You press ok and find yourself back in the list of posts. The time and date of the post was just a few seconds ago. You click on the post to add "one more thing".  And half of the post is gone.
Blogger warned you. So far, there is nothing that can be done. Pressing the back button has saved me a few times in the past but not recently. Especially with browsers driving the Back and Forward button into extinction. (Think about it,  Firefox on PCs don't have the Forward button, Chrome on Android don't have the back button). 
So what should you have done? The moment the dreaded "unsaved changes will be lost" dialog come up, press Cancel. Select all the text in your post, copy and paste them to a text edit (like notepad). There is no other way. That post is Titanic. Pressing save doesn't save it. Pressing ok at the dialog will lose the edits but is the only way to move on. Re-open the post and past back the text. And edit the format. And add the pictures again.  If your are wondering why Blogger didn't take over the world, this is one reason.

Lesson:Don't ignore that "Unsaved changes will be lost" in Blogger.
If Blogger overwrote your post, there is a way to get it back.