Background of the issue:
I am working on a site under development and trying to sync a page with its original language. I usually use the 'Overwrite with [language] content' button for this task. The 'Overwrite with [language] content' button is missing when I edit the page. I opened a ticket earlier and was given instructions to disable plugins and found out that it's the popular Classic Editor plugin that is the cause of the issue. I was able to replicate it in the sandbox environment I was given in the previous support chat. It can be seen when editing this specific page: hidden link. Link to a page where the issue can be seen: hidden link.
Symptoms:
The Copy and Overwrite buttons in the right sidebar are missing.
Questions:
Why are the Copy and Overwrite buttons missing when I edit the page?
How can I resolve the issue caused by the Classic Editor plugin?
Thanks for contacting us. On the sandbox site that we've shared earlier, could you please navigate to WP > Dashboard and share the automatic login link with me as shown in the attached screenshot? This will allow me to log in to check what's going on.