Note a known issue viewing screenshots:
        
          
Issue 21237: Doesn’t record images in real devices.
        
      
      To analyze and visualize the SKP file,
check out the Skia WASM debugger.

How do I retrieve the shader persistent cache from a device?
    
      On Android, you can do the following:
        
adb shell
run-as <com.your_app_package_name>
cp <your_folder> <some_public_folder, e.g., /sdcard> -r
adb pull <some_public_folder/your_folder>

How do I perform a trace in Fuchsia?
    
      See Fuchsia tracing guidelines