Bring back unpublished changes that was accidentally lost

[Chi Nguyen Thuy]

Hi,

While I was working on my document, somehow it's accidentally become a blank page and I couldn't do Ctrl Z to get back. 

When I went to the page again in editing mode, I saw the deleted content under "View changes".

I don't think "Revert to published version" will work because it means I will lost all this strikethrough text.

I wonder whether there is a way to restore all these. Thanks!