Github user bhaisaab commented on the pull request:
https://github.com/apache/cloudstack/pull/489#issuecomment-115341413
With the plugin enabled, only then users are shown a choice of login
options:

Localization example with local login selected:

After user selects a IDP server, they may optionally pass a domain path if
they have multiple accounts across various domains for the authorized IDP
server:

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