Actually, It’s not because of the sticky header. Let me tell you why and how it works.
First of all, You have to understand that the filters are working in the AJAX/Live mode. By default, AJAX works without loading the page and shows the result live.
When AJAX start working it will target the element and once it requests will be complete it will show the targeted element/content so while showing the result it auto scroll at the result which is starting from the 1st row of products.
This is how it works. Hope it makes sense.
Regards 8Themes Team.
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