Google Search Issues

[TerryE]

My Q

I've been an admin on a NFP self-build community forum https://forum.buildhub.org.uk for 10 years, with Google Search Integration for nearly all that period.

The Google search console > Core web vitals reported a fairly flat web page count of just under 30K good URLs until 28 Dec 2025, falling to 2K on the 29th, 500 on the 30th and zero since. Nothing changed on the forum in this post-Xmas period. Did any algo / policy change at the Google side trigger this?

Google Gemini Response

The timing of your data drop is not a coincidence. It aligns perfectly with the conclusion of the Google December 2025 Broad Core Update, which officially began on December 11 and was confirmed as complete on December 29, 2025.

While "nothing changed" on your forum, Google’s internal "yardstick" for quality and performance changed significantly. Here is why your Core Web Vitals (CWV) likely plummeted to zero:

1. Tightened CWV Thresholds

Industry analysis of the December 2025 update indicates that Google "raised the bar" for technical performance. Multiple SEO trackers reported that sites previously sitting on the edge of "Good" were downgraded to "Need Improvement" or "Poor" during this rollout.

• The Shift: If your Largest Contentful Paint (LCP) was hovering around 2.4s (just under the 2.5s limit), the update may have tightened the way Google processes or weights this data, pushing those URLs into the "Need Improvement" category.
• Action: Check the "Need Improvement" or "Poor" tabs in your Search Console. It is highly likely your 30,000 URLs are still there, just reclassified.

2. The "Forum Reassessment" Trend

A notable characteristic of the December 2025 update was a broad reassessment of User-Generated Content (UGC) and Forum sites. While Google previously boosted forums (like Reddit and Quora) in 2024, this update saw a reversal for many.

• CrUX Data Volume: Core Web Vitals are based on the Chrome User Experience Report (CrUX), which requires a minimum threshold of real-user traffic to generate a report. If the core update caused a significant drop in your organic traffic, Google may no longer have enough "field data" to categorize your URLs as Good, Poor, or otherwise, leading to the report showing zero.

3. Sophisticated "Helpful Content" Integration

Google’s systems now more aggressively distinguish between "expert" forum discussions and "thin" or "generic" content.

• The December update intensified scrutiny on E-E-A-T (Experience, Expertise, Authoritativeness, Trustworthiness). For a self-build forum, if Google's updated algorithm now perceives the page experience (e.g., layout shifts from ads or slow loading of forum avatars/scripts) as distracting from the "expert" content, it can negatively impact the Page Experience signals that feed into the CWV report.

Recommended Troubleshooting Steps:

1. Check the "Other" Tabs: Confirm if the URLs moved to "Need Improvement." If they did, a specific metric (likely LCP or INP - Interaction to Next Paint) is the culprit.
2. Compare Traffic (Clicks/Impressions): Go to the "Performance" tab. If your clicks dropped significantly on Dec 28–29, the CWV drop is likely a secondary effect of losing the traffic volume needed for Google to generate the report.
3. Run a PageSpeed Insights (PSI) Test: Run a few of your most popular thread URLs through PageSpeed Insights. This will show you "Field Data" for the last 28 days. If the "origin" summary shows you are failing, you’ll see exactly which metric (LCP, CLS, or INP) changed.
4. INP Focus: Since 2024, Interaction to Next Paint (INP) has been a core metric. Forum software (like XenForo or Invision) can often have high INP due to heavy JavaScript execution during user interactions (like clicking "Reply" or "Like"). The December update placed a higher weight on this specific metric.

Summary: You haven't been "penalized" in the traditional sense, but the December Core Update recalibrated the global standards for "Good" URLs. Your technical performance likely remained the same, but Google's requirements for that "Good" label became stricter on the exact days you saw the decline