Podcast Player: keep rendering when the feed is slow or unreachable

[arcangelini]

Proposed changes

Podcast feeds go down sometimes. When that happened, the Podcast Player block showed nothing at all — even if the same feed had loaded fine minutes earlier.

• We now save the last episode list that loaded successfully and keep it for a week. If the feed stops answering, the block shows that saved copy instead of breaking.
• If the feed answers fine but really has no episodes, we believe it and show the error. Old episodes don't come back from the dead.
• While a feed is down we remember that for 90 seconds, so visitors don't all sit waiting on the same dead request.
• The editor always sees the real error, so a bad feed URL still gets reported to the author instead of being hidden behind old episodes.

Does this pull request change what data or activity we track or use?

No. Feed responses were already cached; this keeps one extra copy of the same data as a fallback.

Testing instructions

• Add a Podcast Player block to a post using a real feed URL, publish, and view the post on the front end. Episodes should render.
• Make the feed unreachable — block the podcast host in your hosts file or firewall.
• Clear the feed's cache so the block has to refetch: wp transient delete --all.
• Reload the post on the front end. The episodes should still render. On trunk the block renders empty here.
• Open the post in the editor. The real error should still appear, so a broken URL is still reportable to the author.
• Unblock the host, clear transients again, and reload. The block should pick the live feed back up.

[github-actions]

Are you an Automattician? Please test your changes on all WordPress.com environments to help mitigate accidental explosions.

• To test on WoA, go to the Plugins menu on a WoA dev site. Click on the "Upload" button and follow the upgrade flow to be able to upload, install, and activate the Jetpack Beta plugin. Once the plugin is active, go to Jetpack > Jetpack Beta, select your plugin (Jetpack), and enable the fix/podcast-latest-episodes-block branch.
• To test on Simple, run the following command on your sandbox:

bin/jetpack-downloader test jetpack fix/podcast-latest-episodes-block

Interested in more tips and information?

• In your local development environment, use the jetpack rsync command to sync your changes to a WoA dev blog.
• Read more about our development workflow here: PCYsg-eg0-p2
• Figure out when your changes will be shipped to customers here: PCYsg-eg5-p2

[github-actions]

Thank you for your PR!

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Follow this PR Review Process:

1. Ensure all required checks appearing at the bottom of this PR are passing.
2. Make sure to test your changes on all platforms that it applies to. You're responsible for the quality of the code you ship.
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Jetpack plugin:

The Jetpack plugin has different release cadences depending on the platform:

• WordPress.com Simple releases happen as soon as you deploy your changes after merging this PR (PCYsg-Jjm-p2).
• WoA releases happen weekly.
• Releases to self-hosted sites happen monthly:
  • Scheduled release: September 7, 2026

If you have any questions about the release process, please ask in the #jetpack-releases channel on Slack.

[jp-launch-control]

Code Coverage Summary

Coverage changed in 1 file.

File	Coverage	Δ%	Δ Uncovered
projects/plugins/jetpack/_inc/lib/class-jetpack-podcast-helper.php	15/262 (5.73%)	-0.74%	30 💔

Full summary · PHP report · JS report

_{If appropriate, add one of these labels to override the failing coverage check: Covered by non-unit tests Use to ignore the Code coverage requirement check when E2Es or other non-unit tests cover the code Coverage tests to be added later Use to ignore the Code coverage requirement check when tests will be added in a follow-up PR I don't care about code coverage for this PR Use this label to ignore the check for insufficient code coveage.}