Safari tab in Chrome and other browsers

Thanks for the clarification. I understand what you're seeing now, and I believe it's what is supposed to occur if you are using "Split View": Open two items in Split View on iPad - Apple Support.

I think what you want to do is to close that other item. Tap the "three dots" indicated in the screenshot excerpt below:

The leftmost icon that appears will move that item to its own space, where you can close it or just forget about it.

I'm not completely certain this addresses your concern though, so if I did not explain it correctly please write back.

Disregard my earlier reply; this is not a "pinned tab". Your question should have been posted in the Using iPad - Apple Community. I'll ask the site Hosts to move it there. There are more experienced iPad users than I in that Community, so perhaps moving it to the right place will elicit more accurate replies.

I don't know how a "Safari tab" could possibly appear in Brave.

Why do you call it a "Safari tab"? Perhaps it is a "Pinned tab"? A "Pinned tab" has no obvious x icon, but you can close it in the universal keyboard shortcut for "close": ⌘ W

You can un-pin a tab by deselecting it in Brave's Tab menu.

If that doesn't help perhaps "Reset settings" in brave://settings/ is applicable.