Bounce rate difference with core metrics and A/B test plugin

Hi,

We use matomo on our website and are currently moving it from legacy tech to a Vue spa. We use the vue-matomo npm plugin for the new app. Recently, we moved our first high traffic page to the new app, and constated that the bounce rate, that historically was around 12%, raised to 18%. This doesn’t feel quite right and I kind of have the feeling that maybe this increase is artificial.

So know we try to determine if the way we redesigned the page was the cause of this difference, or if it is a technical issue, weither it is related to matomo, the SPA, or both.
In order to do that, we bought the A/B test plugin to make some variations on the page. What is weird, is that the 3 versions we tested, including the original that is at 18%, all get between 9% and 11% bounce
rate in the A/B test report. In the meantime, the core metrics continue to indicate around 18%. The A/B test’s bounce is closer to what this page bounce should be, with the elements we dispose.

Which report is right, what justify such a difference, any elements to helps ?

Thanks.

Is it related to the difference explained there?
https://matomo.org/faq/custom-reports/why-is-the-bounce-rate-in-custom-reports-different-to-bounce-rate-in-the-pages-report/

That could indeed explain the difference. So, if I read correctly, the bounce rate seen by a search engine would be closer to the one in custom report, rather than the one in pages ?

Also, shouldn’t the bounce rate in pages be the same than in custom report ? As stated in the example of your link, the « /page1 → /page2 → leave » count as a bounce for page2 in page metrics. If a take the wikipedia description of bounce, it state : « Bounce rate is an Internet marketing term used in web traffic analysis. It represents the percentage of visitors who enter the site and then leave (“bounce”) rather than continuing to view other pages within the same site. »