Hello, MyWhey,
Thank you for contacting us and for using XStore.
We do not have this problem on our tests sites, so please do next tests:
1/ In order to troubleshoot the issue you are experiencing, we suggest that you first try disabling all third-party plugins (including cache plugins) that are not bundled with XStore. You can refer to the following link for a list of included plugins: https://xstore.helpscoutdocs.com/article/36-included-plugins . Additionally, please clear the cache of your browser and check again. It is possible that one of the additional plugins is causing the problem.
2/ If you are using child theme, check how it works when the parent theme is activated.
3/ Select another tabs type in Single product builder and check how it works then.
Let us know the results.
Kind Regards,
8theme team