I'm having a problem with playing flash videos in my application. It's been working before, but ever since Apple has required every developer to enable entitlements and sandboxing, flash videos in the webview do not play. Everytime I disable sandboxing, it works, but if sandboxing is enabled, it doesn't. Below I've posted links images of the Sandboxing and Entitlements settings. Thanks.
figured out how to fix it...
go to your entitlements and add:
KEY: com.apple.security.temporary-exception.mach-lookup.global-name TYPE:Array
then add a string to the array with the value:
com.apple.WebKit.PluginAgent
This sets a temporary exception each time the application is run, giving the app permission to run the PluginAgent.
来源：https://stackoverflow.com/questions/8281666/flash-videos-in-webview-not-working-in-sandboxed-app