Replace existing pages with new pages, keep menu links

I was shocked to see that such a simple thing is not readily supported.

I was even more shocked to see that no one had a good answer here on StackExchange!

Happily, I found this post:

https://wordpress.org/support/topic/updating-current-page-with-new-built-page/

…and am grateful for the answer provided by Joy (@joyously on WordPress.org and Slack)

“If you need to build a new version over a long period of time, start a new page and only save Draft. [You can also save and publish as another page name so others can review it while under construction.] When it is ready, go into the Text mode of the editor and copy all. Then go to the old page Text mode and select all, and paste. Then save the old page (with new content).”

So:

  1. Use the text-mode editor to copy the content of the new page.

  2. Open the old page, go to text-mode editor and paste the copied content from the new page.

Enjoy!