Xcode 12.3 iOS 14.3 simulators Yellow Dock / yellow translucent issues

Question

Today I downloaded the release of Xcode 12.3, and I went running the iOS 14.3 simulators and it seems like there is a graphic glitch that all translucent views are yellow, dock included.

I redownloaded iOS 14.2 and those seem fine. It just seems really odd. I've submitted feedback, but I was curious if anyone else has seen this?

I'm on macOS v10.15.7 (Catalina) and am curious of if it's just Catalina or also macOS v11 (Big Sur).

Answer 1

Xcode 12.4 RC has announced fix.

iOS simulated devices no longer display an incorrect yellow tint in translucent UI elements. Certain GPUs may continue to display the tint with some tvOS simulators. (71203015)

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I think it is a bug related to the discrete GPU.

In addition, this bug causes the background of the on-screen keyboard to be almost RGB(0,0,0). Experienced on MBP 2017 with Catalina.

Workaround I - Using integrated GPU

1. In the simulator, set menu File → GPU Selection → Prefer Integrated GPU to work around this bug.

2. Restart the simulator.

This was tested on a MacBook Pro with Catalina and Big Sur. As comments suggest that it won't work on iMac.

Workaround II - Reduce transparency

In the simulated device (e.g. iPhone), Settings → Accessibility → Display & Text Size → turn on Reduce Transparency.

Notice that it can only reduce the previous 'solid' yellow to 'fairly light'.

I find this workaround, as the discrete GPU can be used, is more suitable for testing the UI logic than the previous solution.

This was tested on a MacBook Pro with Catalina. Might work on iMac.

Answer 2

Are you using a MacBook Pro? I had the same bug.

I solved in the following ways.

• Step 1: Unplug all cables, including the charging cable
• Step 2: Restart the iOS simulator