Meny unknow

Is Settings > Accessibility > Touch > Reachability enabled?

You’re probably swiping your finger off downwards off the bottom of the screen?

That’s then sliding the display screen lower, to make the controls on the upper end of the display easier to reach.

Tap the top to cause the screen to return to its centered position.

This gesture works everywhere within an iPhone, when the gesture is enabled, and is not restricted to use in Safari.

These two people stand for all those Apple employees, that provide Support for the users clicking on the link right next to the photo:

Get Support

The photo is the same on every Official Apple Support page in different countries: