YSK: If you updated to the latest version of iOS 15 and don’t like the search bar living at the bottom of the UI in Safari you can tap the “aA” symbol and move it back up to the top.
from /r/YouShouldKnow
YSK:如果你更新到最新版本的iOS 15,不喜欢Safari浏览器中生活在用户界面底部的搜索栏,你可以点击 "aA "符号,将其移回顶部。