Flutter not rendering text after sitting idle (iOS) #57676
Description
We are experiencing an issue in the 1.17.1 stable release. Our application appears to render all views correctly when the application is initially run. However, we discovered in our TestFlight builds that once the application has been sitting idle in the background for a while, text rendering becomes very broken.
I assume this is somehow related to the Metal transition. I was able to downgrade to 1.15.4, and we didn't experience the issue there.
This is a major issue that will prevent us from releasing using the newest version of Flutter.
Details
We've seen this on at least iPhone X and 11 iOS 13.4.1 physical devices.
We've never seen the issue in a simulator.
I wish I could give you an exact path to recreating this, but it's one of those issues that takes time to reveal itself. So frustrating, I know...
[✓] Flutter (Channel stable, v1.17.1, on Mac OS X 10.15.4 19E287, locale en-US)
• Flutter version 1.17.1 at /usr/local/flutter
• Framework revision f7a6a7906b (8 days ago), 2020-05-12 18:39:00 -0700
• Engine revision 6bc433c6b6
• Dart version 2.8.2
[✓] Android toolchain - develop for Android devices (Android SDK version 28.0.3)
• Android SDK at /Users/aaronscherbing/Library/Android/sdk
• Platform android-29, build-tools 28.0.3
• Java binary at: /Applications/Android Studio.app/Contents/jre/jdk/Contents/Home/bin/java
• Java version OpenJDK Runtime Environment (build 1.8.0_212-release-1586-b4-5784211)
• All Android licenses accepted.
[✓] Xcode - develop for iOS and macOS (Xcode 11.4.1)
• Xcode at /Applications/Xcode.app/Contents/Developer
• Xcode 11.4.1, Build version 11E503a
• CocoaPods version 1.8.4
[!] Android Studio (version 3.6)
• Android Studio at /Applications/Android Studio.app/Contents
✗ Flutter plugin not installed; this adds Flutter specific functionality.
✗ Dart plugin not installed; this adds Dart specific functionality.
• Java version OpenJDK Runtime Environment (build 1.8.0_212-release-1586-b4-5784211)
[!] IntelliJ IDEA Ultimate Edition (version 2019.3.1)
• IntelliJ at /Applications/IntelliJ IDEA.app
✗ Flutter plugin not installed; this adds Flutter specific functionality.
✗ Dart plugin not installed; this adds Dart specific functionality.
• For information about installing plugins, see
https://flutter.dev/intellij-setup/#installing-the-plugins
[✓] VS Code (version 1.45.1)
• VS Code at /Applications/Visual Studio Code.app/Contents
• Flutter extension version 3.10.2
[✓] Connected device (2 available)
• Aaron’s iPhone 11 • 00008030-00040C241AFA802E • ios • iOS 13.4.1
• iPhone X (iOS 12) • 1F4591EB-ADF4-479D-9D58-C83861AE09D8 • ios • com.apple.CoreSimulator.SimRuntime.iOS-12-2 (simulator)