- Rewrote XHR handling with a new Cypress XMLHttpRequest object, fully qualified URLs, initiator stack, and enhanced logging and network tab visibility.
- Breaking changes include a different XHR alias return type and deprecation of requestJSON/responseJSON and cy.respond, requiring updates to assertions.
- Added features such as disabling servers mid‑test, stubbing control via {stub:false}, configurable XHR defaults, automatic content‑type headers, plus numerous bug fixes.