[Firefox] Removing cookie failed: Cookie did not include a name

[Serveny]

Current behavior

If setting a cookie without a name, cypress running under firefox is unable to delete the cookie the next time running the test. Every test after this will fail.

Desired behavior

Cypress should clear all cookies, regardless if it has a name or not.

Test code to reproduce

describe('BugReproductions', () => {
  it('Can handle broken cookies', () => {
    // Unnamed cookie
    cy.setCookie('', `[{"id":"test-data-1","title":"Test Data 1"}]`);

    cy.visit('/');
  });
});

Cypress Version

13.15.0

Node version

v22.2.0

Operating System

Windows 11

Debug Logs

Removing cookie failed for: {"domain":"localhost","httpOnly":false,"name":"","path":"/","sameSite":"no_restriction","secure":false,"value":"[{"id":"test-data-1","title":"Test Data 1"}]","expirationDate":2359029695}. Cookie did not include a name

Other

I need this to reproduce a bug, where I got an unnamed cookie and it broke my web application.

[jennifer-shehane]

@Serveny We're calling cookies.remove(), which requires a name be provided to remove cookies, otherwise it throws an error which we are surfacing here. I don't think there's a way to actually remove a cookie that does not have a name, so I'm not sure what we could do here.

[Serveny]

Thanks for the fast answer!

This is indeed a strange behavior of the browser. I did some testing and the only way to remove the nameless cookie is to set the expiration date in the past. You could do this in Cypress with the following code:

cy.setCookie('', `xyz`, { expiry: -1 });

The cookie content is then overwritten with “xyz” (it must contain some value, otherwise the browser rejects the call) and deleted directly. Could this call be integrated before the reset function?

[Serveny]

I also noticed that deleting via cy.setCookie('', 'xyz', { expiry: -1 }); only works if there are no other cookies. So it should be called after the cookie reset via api.

[jennifer-shehane]

@Serveny This is something we could consider and monitor feedback on needing. It's not something we'll be prioritizing right now.

[emuecksch-sz]

We experience the same issue after upgrading from 13.13.3 to 13.14.2, the problem persists on 13.15.0.

The error message is:

Removing cookie failed for: {"domain":".connectad.io","httpOnly":false,"name":"","path":"/","sameSite":"no_restriction","secure":true,"value":"cadsync","expirationDate":1728648605}. Cookie did not include a name

We also do not control the cookie as it is set by one of our ad providers.

Could you maybe change the behavior to log a warning instead of exiting the test run?