I understand that making [user-agent hints][1] more ambiguous is intended, in part, to make [browser fingerprinting][2] harder.

My own (Windows desktop) Chrome sends the headers:
```
user-agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.75 Safari/537.36
sec-ch-ua: &quot;Chromium&quot;;v=&quot;86&quot;, &quot;\&quot;Not\\A;Brand&quot;;v=&quot;99&quot;, &quot;Google Chrome&quot;;v=&quot;86&quot;
sec-ch-ua-mobile: ?0
```

What I don&#39;t get is:
 1. Why the string &quot;Not A Brand&quot; specifically? Does anyone else use this pseudo-UA? Is this a joke of some sort?
 2. Why the `\&quot;` and `\\A;` inside the string? My only guess is that this is supposed to mess with parsers somehow (like the anti-IE hacks in CSS), but that seems like a rather odd purpose — and IIRC, `\A` is the bell character.
 3. How is this supposed to accomplish user-agent hint ambiguity, given that it *also* sends the full `user-agent` header, which has the specific version numbers?
 4. While at it: why does Chrome&#39;s user-agent also claim to be Mozilla, AppleWebKit, and Safari? It isn&#39;t, and this `user-agent` string is distinctively Chrome&#39;s. Does it have some sort of embedded components from those other browsers?

  [1]: https://github.com/WICG/ua-client-hints
  [2]: https://panopticlick.eff.org/

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Why does Chrome use sec-ch-ua: "\"Not\\A;Brand";v="99"?