It scrolls fine on Safari on iPhone without ad block. It's possible that it's a combination of: - it's known that iPhone and mobile Safari prioritize user int

It scrolls fine on Safari on iPhone without ad block. It's possible that it's a combination of: - it's known that iPhone and mobile Safari prioritize user interaction over display fidelity. So Safari prioritizes scrolling over rendering updates, and updates whatever's lagging at more infrequent intervals - Safari implements CSS var updates differently (see https://news.ycombinator.com/item?id=29353136 https://news.ycombinator.com/item?id=29353136 on what's going on with the site)