Google says the dead source links on Discover’s AI summary cards were not a deliberate product change. They were “a bug in a Discover experiment,” and the experiment has now been shut off.
Rajan Patel, VP of Engineering for Search at Google, confirmed the rollback in a reply on X on Monday evening. He was answering Lily Ray, who had shared a report from independent researcher Damien Andell.
What was happening
Andell found that Discover was testing an AI summary change that disabled clicks on sources. Normally, tapping a summary’s sources opened a feed of articles from those sources — one path from an AI summary to the sites it cites.
He spotted the test through a flag called “disable_aio_sources_button_tap.” That flag stopped taps on the source icons at the bottom of the card from opening the article feed.
Google’s response
“Hey Lily – this was a bug in a Discover experiment. We’ve turned off the experiment, and the experience works as intended again.”
The reply didn’t say what the experiment was testing, how long it ran, or how many users saw the disabled taps. On Oct. 27, Andell checked again and said the experiment had been removed and replaced with another called “aio tap falls through to hero.” His post didn’t explain how the new experiment works or where it is running.
Why this matters for publishers
Discover is a meaningful source of non-brand visibility, and AI summaries are reshaping that traffic. That source tap was a direct route from a summary to a specific site’s articles. If it breaks, a cited source can be visible in the AI summary without an easy next step.
The metric to watch in Search Console is narrower than it may look. The Discover generative AI report records impressions — when a user sees links to your pages through the generative AI capabilities in Discover. It does not count a source tap. That means the report would not have shown this bug directly; it would have shown the impression, not the blocked action.
What to do now
- Open your Discover feed and tap the source icons on an AI summary card to see whether the article feed opens.
- Watch the Discover generative AI report for impressions in the AI summary.
- Treat silent changes as experiments — Google often tests and rolls back without a public note.
Until Google or Andell explains the replacement experiment, a quick manual check is the best signal.
Source: Search Engine Journal
