I have seen posts such as Cypress - run test in iframe for how to handle iframes in Cypress. I am still chewing on that, but even more old and outdated are plain old frames, which is what a legacy system (that I have to test) uses.
I have checked Github -Cypress iframes which is recommended by Cypress, but haven't found an answer for plain old frames. Using the solution for iframe, hasn't worked.
The problem is the same as with an iframe where, when trying to select an element using
cy.get('input').type('test');
you receive an AssertionError stating the typical:
Timed out retrying after 4000ms: Expected to find element: input, but never found it.
Any advice is appreciated.