Recommended Updates email is showing duplicate content

Issue Summary

The recommended updates email sent either daily or weekly from Confluence is showing duplicate content under "Most Popular"

This is reproducible on Data Center: Yes

Steps to Reproduce

1. Deploy a confluence server
2. Create 3 pages with content.
3. Add a different number of comments to each page - the more comments a page has, the more popular it is deemed to be.
4. Go to scheduled jobs and manually run the “Send Recommended Updates Email” *Ensure it is between 13:00 and 13:59 system time otherwise the email will not be sent.

Expected Results

A "Recommended in Confluence" email received with the 3 pages displayed in order of number of comments added - their "popularity":

Actual Results

The most popular page is shown twice in the email, and then the second most popular page is displayed:

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available