Tor Browser 8.0 wrong user-agent

Tor Browser 8.0 does not set user agent properly.

general.useragent.override = Mozilla/5.0 (Windows NT 6.1; rv:60.0) Gecko/20100101 Firefox/60.0

User agent shown using https://httpbin/user-agent = Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Firefox/60.0

Expected behavior: User agent should match the general.useragent.override string and should not reveal OS details

Additional details: OS is Arch Linux. Installed via AUR package tor-browser-en. New install. No settings changed.

Trac:
Username: temp123

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