By default, WordPress doesn't offer a way to see what old revisions look like. To preview old revisions of your content, install the PublishPress Revisions plugin.
When you are editing a post, click the “Revisions” link in the right sidebar:
You are now looking at revisions for a post, and you'll see a “Preview/Restore” link.
This will take you to the front of your site where can see your revision. There will be a bar across the top of the page saying, “This is a Past Revision”. You will have three choices:
- Compare: see how this revision compares to the current version.
- View Published Post: see the current version live on your site.
- Restore: replace the current version with this older revision.