1: To reboot your Android device into safe mode, hold the power button until the power menu shows up.
2: long-press the “Power off” menu item, until you see a dialog box, asking if you want to reboot your device into safe mode.

Notes- When the device is booted in safe mode, the words “Safe Mode” will appear in the bottom-left corner of the screen.

How to Troubleshoot Device in Safe Mode

in Safe Mode all third-party applications, widgets, and any other customizations will be disabled. In the meantime Android system will allow you to uninstall any of the installed apps that cause system stability issues.
To exit safe mode you should restart your device normally.
Press device’s power button and then tap “Power off” menu. Then turn on the device and it will boot in a standard mode.

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