Assert the account menu of the header lists (or does not list) a link, by its text: "Login" for a visitor, "My account" and "Log out" for a signed-in account.
Examples
Then the account menu should list "Log out"
Then the account menu should list "My account"
And the account menu should not list "Login"
Then the account menu should contain "Login"
And the account menu should not contain "Log out"
Pattern
Then(/^the account menu should( not)* (?:list|contain) "([^"]*)"$/, …)
Part of @webship-js/backdrop-cms-steps (github.com/webship/backdrop-cms-steps), a step pack for Webship-js 2.0.x.