Our team is aware of the current performance issues of web applications running on iOS (any browser) or Safari (macOS). Our customers report about a 3x performance degradation compared to running in Chrome on Windows, Linux, or macOS. While for most projects web applications are still usable with degraded performance, we are looking for ways to improve performance.
We still have not determined the root cause of the issue with WebKit browsers. Currently, we are investigating how Safari works with nested web workers and postMessage/MessageChannel, but due to the lack of extensive debugging tools in Safari, we have not achieved any significant results.
Any ideas or help with low-level WebKit/Safari debugging are welcome. If you can help us, please reach out to me.