Huawei Mate 9 - Manual (Page 196)

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Enabling shortcuts for accessibility features
Use the power button to quickly enable accessibility features.
1
Open Settings.
2
Touch Advanced settings > Accessibility and select Accessibility shortcut.
3
Switch on Accessibility shortcut. You can enable accessibility features in two ways:
l
a
Hold down the power button until you hear a confirmation tone or your phone vibrates.
b
Touch and hold the screen with two fingers until you hear a confirmation tone.
System Features and Settings
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