Cypress 10x does not honor returned xhr when submitting form

[fusionshoes]

Hey all.
I've been seeing an issue on cypress v10x (since 9.2, actually). When I submit a form the xhr target page is not loaded.
Instead, the current page I'm on is re-loaded.
I'm curious if others have seen this XHR issue, where a page does not redirect properly...?

I know there's not a ton of detail here, but any thoughts or ideas very much appreciated. I'm using cypress v9.1.1 successfully, and I realize it will likely sunset at some point, so I'm hoping for resolution.

Example (add a new user):

• on a page (/users, for ex), add all info for that user
• click on the Add User button (or alternatively use .submit()
  Actual Result:
• the current /users page simply reloads, with all fields blank when clicking Add User button
• if using .submit() on the form, the json blob from the server is returned into the page (the add user page is not reloaded, just the blob). In that blob, the redirect to the correct page is shown (the app should load the new users page. For example: /users/50, indicating the user id). This tells me the server side is processing properly.
  Expected Result:
• the /users/50 page should load upon either submission method

Notes:

• there are a couple issues out there touching this:
  • cancel XHR's optimistically #3974 ("cancel XHR's optimistically", which contains zero detail on what is actually happening)
  • https://stackoverflow.com/questions/60385480/cypress-canceling-an-api-request-upon-a-form-submit ("cypress canceling an api request upon a form submit"). I tried the solution offered in this thread with no luck
• I have verified with our dev team that the returned json blob is correct. They were unable to determine exactly why the page would not redirect within cypress.
• I've tried headed/headless, diff browsers, code isolation, diff environments, completely new installs in diff locations, etc, and have not been able to resolve this.