That’s side bar. Turn it off if you don’t want it. Otherwise customize it.
brave://settings/appearance has option for not only turning that off or making it appear only on mouseover, but it also has option for a button to appear on the top right of your browser to turn it on.
Hello @Aaa2, thanks for contacting us. This is the way it works
at the right top corner > 3 bars icon > show sidebar > we can choose between
On mouseover -
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