+--------------------------------------+
     | Browser                              |
     |                                      |
     | +----------------------------------+ |
     | | https://calling-site.example.com | |
     | |                                  | |
     | |        Calling JS Code           | |
     | |               ^                  | |
     | +---------------|------------------+ |
     |                 | API Calls          |
     |                 v                    |
     |          PeerConnection              |
     |                 ^                    |
     |                 | API Calls          |
     |     +-----------|-------------+      |   +---------------+
     |     |           v             |      |   |               |
     |     |       IdP Proxy         |<-------->|   Identity    |
     |     |                         |      |   |   Provider    |
     |     | https://idp.example.org |      |   |               |
     |     +-------------------------+      |   +---------------+
     |                                      |
     +--------------------------------------+