Issue Summary

When you enter RSS feeds into an RSS feed validator, they may fail validation. This means there are errors in the RSS feed that could prevent it from updating in certain RSS readers. Currently, this issue is occurring with the official Slack RSS app.

Steps to Reproduce

1. Visit https://status.zoom.us/
2. Click "Subscribe to Updates" and Select the RSS icon.
3. You will get the URL of the RSS Feeds as https://status.zoom.us/history.rss
4. Enter the RSS Feed URL in Feed Validator URL: https://validator.w3.org/feed/, here is the readied URL: https://validator.w3.org/feed/check.cgi?url=https%3A%2F%2Fstatus.zoom.us%2Fhistory.rss

List of Errors

1. line 13, column 6: Undefined item element: maintenanceEndDate (13 occurrences)
2. line 10, column 0: description should not contain data-var attribute (173 occurrences)
3. line 221, column 2: Missing atom:link with rel="self"

Expected Results

RSS passes validation and does not stop updating

Actual Results

RSS feed fails validation and stop working after adding it to a reader

Workaround

None at this time