Reading https://github.com/symfony/symfony/blob/master/UPGRADE-3.3.md I got linked to http://symfony.com/doc/current/components/http_foundation/trusting_proxies.html which opens the 3.2 version for me (local problem or website issue). Would have expected 3.3, but 3.2 is marked as current.

After switching to the 3.3 docs I'm reading:

Request::setTrustedProxies(array('192.0.0.1', '10.0.0.0/8'));

Imho that required the header names as second parameter now.

Also, the upgrade doc says

The Request::setTrustedHeaderName() and Request::getTrustedHeaderName() methods are deprecated, use the RFC7239 Forwarded header, or the X-Forwarded-* headers instead.

yet the examples still show

Request::setTrustedHeaderName(Request::HEADER_FORWARDED, 'X-Forwarded');

So bottom line- 3.3 docs seem out of sync regarding this BC change?