Retrieving content properties from the REST API returns inconsistent results

Issue Summary

The get content properties API] returns inconsistent results. For further context, see https://community.developer.atlassian.com/t/rest-api-changes-for-content-properties/39894.

Steps to Reproduce

1. Log into a Confluence tenant and visit any page.
2. From the URL, extract the content ID.
3. Visit [tenant-base]/wiki/rest/api/content/{id}/property and observe the response JSON.
4. Visit [tenant-base]/wiki/rest/api/content/{id}/property?expand=version and observe the response JSON.
5. Visit [tenant-base]/wiki/rest/api/content/{id}/property?expand=content and observe the response JSON.
6. Wait 10 minutes.
7. Visit [tenant-base]/wiki/rest/api/content/{id}/property?expand=content and observe the response JSON.
8. Visit [tenant-base]/wiki/rest/api/content/{id}/property?expand=version and observe the response JSON.
9. Visit [tenant-base]/wiki/rest/api/content/{id}/property and observe the response JSON.

Expected Results

All responses are in accordance with the API documentation].

Actual Results

1. The responses for steps 3, 4 and 5 are identical. They all include expanded version information, even though this should not be provided for 5 where expand=content.
2. The response for step 7 is correct (includes expanded content).
3. The response for step 8 is an internal error (500 status code).
4. The response for step 9 is an internal error (500 status code).

Workaround

"Get content properties" API can be used instead of "Get content property"