Opening Warning / Yellow Box details ui spikes CPU usage in iOS

[xzilja]

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• Search for existing issues: https://github.com/facebook/react-native/issues
• Use the latest React Native release: https://github.com/facebook/react-native/releases

Environment

  React Native Environment Info:
    System:
      OS: macOS 10.14
      CPU: x64 Intel(R) Core(TM) i7-8750H CPU @ 2.20GHz
      Memory: 51.45 MB / 16.00 GB
      Shell: 3.2.57 - /bin/bash
    Binaries:
      Node: 10.11.0 - /usr/local/bin/node
      Yarn: 1.10.1 - /usr/local/bin/yarn
      npm: 6.4.1 - /usr/local/bin/npm
      Watchman: 4.9.0 - /usr/local/bin/watchman
    SDKs:
      iOS SDK:
        Platforms: iOS 12.1, macOS 10.14, tvOS 12.1, watchOS 5.1
    IDEs:
      Xcode: 10.1/10B61 - /usr/bin/xcodebuild
    npmPackages:
      @types/react: 16.4.18 => 16.4.18 
      @types/react-native: 0.57.7 => 0.57.7 
      react: 16.7.0-alpha.0 => 16.7.0-alpha.0 
      react-native: 0.57.4 => 0.57.4 
    npmGlobalPackages:
      react-native-cli: 2.0.1

Description

Opening / Expanding warning notification to view fullscreen message causes massive CPU spike that persists and starts heating up my mac until that view is closed.

Just warning notification

Viewing full details

Reproducible Demo

Simply add console.warn("Test") anywhere in your application and open details view.

[orta]

This was definitely happening to me on a production build of RN, but when I tested in master on RNTester I couldn't repro.

0.59:

Master:

[cpojer]

Closing as it isn't happening on master any more. Happy to reopen if it is still an issue.

[ravirajn22]

The issue still occurs in 0.60.5 version of react-native, it wont happen every time but 40% of the time. When it happens you can see the yellow box at the bottom vibrating(small but visible). Its a serious issue where it pushes the mac to over 200% CPU usage, if not careful could seriously affect machines long time performance. Tested on emulator iPhone Xr in a new project. Not attaching image because its easily reproducible. @cpojer