Cypress single-tab architecture vs OAuth redirect flows requiring new browser contexts

Testing OAuth flows that spawn new tabs

Applications using OAuth providers often redirect users to a new browser tab or popup window for authentication. Cypress runs all tests within a single browser context and does not expose APIs to switch control to a newly opened tab. The documented workaround is to stub window.open and simulate the redirect in the same tab, but this bypasses the actual provider UI and any cross-origin cookie handling.

Constraint: no native multi-context support

The runner and the application under test share one JavaScript event loop. cy.origin() enables cross-origin iframe interaction, yet it does not extend to top-level windows created by window.open() or target="_blank" links. Experimental flags and community plugins exist, but their stability across Cypress versions is unclear.

Given that stubbing avoids the real redirect, what is the recommended strategy for validating the complete OAuth handshake—including provider consent screens and token exchange—when the provider mandates a separate top-level browsing context? Are there version-specific flags or supported patterns that let a test follow the redirect without leaving the Cypress runner? How do teams currently verify the post-redirect application state when the authentication completes in a window Cypress cannot control?