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Usually, the communication between native and the app is done via sending intents to either broadcast or activity. These communication channels are for launching root requests dialogs, sending root request notifications (the toast you see when an app gained root access), and root request logging. Sending intents by am (activity manager) usually requires specifying the component name in the format of <pkg>/<class name>. This means parts of Magisk Manager cannot be randomized or else the native daemon is unable to know where to send data to the app. On modern Android (not sure which API is it introduced), it is possible to send broadcasts to a package, not a specific component. Which component will receive the intent depends on the intent filter declared in AndroidManifest.xml. Since we already have a mechanism in native code to keep track of the package name of Magisk Manager, this makes it perfect to pass intents to Magisk Manager that have components being randomly obfuscated (stub APKs). There are a few caveats though. Although this broadcasting method works perfectly fine on AOSP and most systems, there are OEMs out there shipping ROMs blocking broadcasts unexpectedly. In order to make sure Magisk works in all kinds of scenarios, we run actual tests every boot to determine which communication method should be used. We have 3 methods in total, ordered in preference: 1. Broadcasting to a package 2. Broadcasting to a specific component 3. Starting a specific activity component Method 3 will always work on any device, but the downside is anytime a communication happens, Magisk Manager will steal foreground focus regardless of whether UI is drawn. Method 1 is the only way to support obfuscated stub APKs. The communication test will test method 1 and 2, and if Magisk Manager is able to receive the messages, it will then update the daemon configuration to use whichever is preferable. If none of the broadcasts can be delivered, then the fallback method 3 will be used.