Hello, 鄭竣丰
According to the fact, it is not shown on our demos means that it is local problem on your website. We recommend that you take the following steps to troubleshoot the problem:
1/ Disable extra plugins and recheck. You may leave only Elementor, WooCoomerce, XStore core.
2/ Check the issue in another browser (maybe it is related to your browser version)
3/ You may create a simple page with minimum heavy content (simple text is better) and check that page from your side. It could help to find if the issue is related to some specific Elementor widgets or if it is a global scroll issue on your website.
Kind Regards,
8theme team
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