Canvas performance slow on Safari, iPad 10 only

This is my first time to post on this forum. If there are something we didn't notice, please tell me. Thanks.

Background

We're using canvas to provide a web component to marketing. https://demo.mescius.jp/spreadjs/BenchmarkSample/

Problem

Recently we have met an issue from customer. He is using iPad 10th to access the web component but when he tries to scroll it and it's very slow on iPad 10th. His iPad OS version is 17.7 and this issue also can be reproduced on our iPad 10th with iPad OS 18.0.1. But if we use iPad 9th with iPad OS 17.7 and 18.0.1, things are fine and there isn't any performance issue.

We developer took some time investigating and found it's because of iPad 10th's safari takes longer time to paint each frame. On iPad 9th, it needs nearly 10ms to paint each frame. But on iPad 10, it needs nearly 70ms to paint each frame.

Also we can provide simple code for you to check the different. We tried to simulate the repaint when user is scrolling. You can see on iPad 9th, it will be 2~3ms but on iPad 10th, it will be more than 10ms for each frame.

It has been happening on iPad 10th only with iPad OS 17.6/17.7/18.0. This will be a big problem for us because it means on the iPad 10th (the latest iPad, non Pro or Air), it can't be used.

Question

Is there anyone knowing similar issue with this one? And do you know how to solve it on iPad 10?

Canvas performance slow on Safari, iPad 10 only
 
 
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