USB Debug Guard is a root-only tool for long USB debugging sessions. It protects the display while keeping ADB reachable, then restores the previous display settings when protection stops. Features • Detects USB data connections and ADB state through Android system APIs, without routine Root polling. • Turns the screen off while keeping ADB reachable, or keeps it awake at minimum brightness for devices that lose ADB when the display sleeps. • Saves and restores the previous display settings. • Can lock the device after USB disconnects. • Runs only after you enable its foreground service. • Stops automatic Root work after a denial, timeout, exception, or process cleanup failure, preventing an endless su retry loop. • English and Simplified Chinese. Requirements • A working Root manager such as Magisk or KernelSU, able to run Android settings and input commands. • A USB data connection. A charge-only cable or charger does not start protection. Root behavior varies between devices, OEM firmware, and Root managers. Test the app on a non-critical device before relying on it for unattended sessions.