Layers flickering/disappearing on iOS

Description

I'm currently using an IconLayer (with custom svg) and a PathLayer, these are basically some markers that represent a vehicle, while the PathLayer draws the route.

This seems to work great on Windows/OSX/Android, however, there are some rendering issues on iPhone (IOS 15.0), these issues are different based on the version of deck.gl:

• 8.5.8 - both layers flicker when there's data changes happening
• 8.6 - IconLayer does not appear at all (there is no flickering)

One more interesting thing, when I change the PathLayer to be drawn on top of IconLayer, it works properly, but it's not the behaviour that we want.

I expect the layers to work exactly like on the rest of devices, without any flickering.

Repro Steps

I extracted this codepen from our application.

1. Open codepen link on an iPhone
2. Wait a couple of seconds until data is updated (there's a timer that updates to random coordinates every 5 seconds)
3. Notice error

This codepen uses deck.gl version 8.5.8, you can change the script to use the latest version https://cdn.jsdelivr.net/npm/deck.gl@latest/dist.min.js so you can see the difference.

Environment

• Framework Version: deck.gl 8.5.8 / deck.gl 8.6
• Browser Version: Safari 15
• OS: iOS 15.0

Logs

Start by opening the linked CodePen on an iPhone running iOS 15 and compare deck.gl 8.5.8 with 8.6 or the latest version. Focus on the IconLayer and PathLayer while the data updates every five seconds, and compare layer ordering. Done means both layers render consistently without flickering or disappearing, matching behavior on other devices.