Thanks for sharing that you run into the same issue. Agree that something is wrong, perhaps scrolling causes the table to re-render for some reasons. I will look more into it and getting it fix next. There are techniques to optimize performance such as only render visible rows. I haven't spent much time testing it on mobile web and will enhance the mobile web view & experience upcoming.
You don't need to only render visible rows. There are only 400. You just insert them into the Dom and that's it.