Not sure the privacy browser app itself really "includes" those tools as they work outside the browser on some SaaS somewhere. The browser sends users' data to a service (to get/handle a short URL) which then knows who else visits that URL; and to a service somewhere that gets in the middle of their email. Both of these introduce new actors who themselves should be evaluated for security, privacy, or other threat.

Note that the venerable iCab for iOS allows setting useragent and effectively anything and everything else one could want to tinker with in a browser, as does Kagi's Orion which also supports Chrome and Firefox extensions.

Finally, there's a difference between privacy, anonymity, and security, just as there's a difference between government surveillance, adtech surveillance, and threat actors exploiting weaknesses in opsec. When advertising privacy-focus, it's important to say what you're doing, and what you're not doing, as Google Chrome learned when having to pay $5B for letting users be confused about "incognito" mode:

https://www.reuters.com/legal/google-settles-5-billion-consu...

PS. The reply paragraph above from "When comparing..." to "and a URL shortener." sounds LLM generated. The second paragraph sounds human written.