Huawei P10 PLUS User Manual page 36

By default, screenshots are stored in Gallery, within the Screenshots folder.
Touch to share a screenshot.
Taking scrolling screenshots
Use knuckle gestures or scrolling screenshots to capture content that does not fit on the screen.
This is useful for sharing chat conversations, web pages, or large images.
Using the shortcuts tab
1
Open the notification panel, and then touch
2
After taking the screenshot, touch
3
The screen will scroll down automatically as your device captures a screenshot.
to take a standard screenshot.
to take a scrolling screenshot.
Screen and Display
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