Main issue: Mobile pages intermittently show high Total Blocking Time (TBT) on first load, then improve on subsequent loads. TBT is a metric indicating how long the main thread is blocked by scripts, delaying interactivity.
Initial review: A respondent ran PageSpeed Insights for the homepage and did not observe the high TBT shown in the screenshot. They requested the exact page and analysis links where the issue occurs for targeted guidance.
Update from site owner: The problem appears on multiple pages, notably a product page, and seems tied to first-load conditions (cold cache). They shared both the live URL and a PageSpeed Insights report link for that page.
Current response: The helper offered assistance to reduce TBT but provided no concrete, technical steps yet. No specific causes (e.g., render-blocking JS, long tasks, third-party scripts) were identified in-thread.
Status and next steps: Discussion remains open. Further analysis of the provided product page’s first-load metrics is needed, focusing on script execution and main-thread long tasks. The shared screenshot is relevant, but reproducibility varies by page and run.
Hello Jscicluna,
We have checked pagespeed analysis with the link you provided and we are not getting much high tbt like you attached.https://pagespeed.web.dev/analysis/https-driftndrive-com-au/7ksq4f7l5u?form_factor=mobile
Can you please share link of the page in which you are facing the issue ? and analysis link too.
So we can check and give you relevant suggestions.