diff --git a/packages/driver/cypress/e2e/e2e/origin/commands/aliasing.cy.ts b/packages/driver/cypress/e2e/e2e/origin/commands/aliasing.cy.ts
index 0b879b654f6b..e225b4270f97 100644
--- a/packages/driver/cypress/e2e/e2e/origin/commands/aliasing.cy.ts
+++ b/packages/driver/cypress/e2e/e2e/origin/commands/aliasing.cy.ts
@@ -17,14 +17,14 @@ context('cy.origin aliasing', () => {
 
     it('fails for dom elements outside origin', (done) => {
       cy.on('fail', (err) => {
-        expect(err.message).to.equal('`cy.get()` could not find a registered alias for: `@welcome_button`.\nYou have not aliased anything yet.')
+        expect(err.message).to.equal('`cy.get()` could not find a registered alias for: `@link`.\nYou have not aliased anything yet.')
         done()
       })
 
-      cy.get('[data-cy="welcome"]').as('welcome_button')
+      cy.get('[data-cy="cross-origin-secondary-link"]').as('link')
 
       cy.origin('http://foobar.com:3500', () => {
-        cy.get('@welcome_button').click()
+        cy.get('@link').click()
       })
     })
   })
diff --git a/packages/driver/cypress/e2e/e2e/origin/cookie_login.cy.ts b/packages/driver/cypress/e2e/e2e/origin/cookie_login.cy.ts
index 4910d7b4948b..f5c251013c42 100644
--- a/packages/driver/cypress/e2e/e2e/origin/cookie_login.cy.ts
+++ b/packages/driver/cypress/e2e/e2e/origin/cookie_login.cy.ts
@@ -34,6 +34,11 @@ describe('cy.origin - cookie login', () => {
     cy.get('h1').invoke('text').should('equal', 'No user found')
   }
 
+  beforeEach(() => {
+    // makes it nice and readable even on a small screen with devtools open :)
+    cy.viewport(300, 400)
+  })
+
   /****************************************************************************
     Cookie Login Flow
     - localhost/fixtures/primary-origin.html:
@@ -107,17 +112,6 @@ describe('cy.origin - cookie login', () => {
       verifyLoggedIn(username)
     })
 
-    it('makes cross-origin cookies readable via document.cookie', () => {
-      cy.visit('/fixtures/primary-origin.html')
-      cy.get('[data-cy="cookie-login"]').click()
-      cy.origin('http://foobar.com:3500', { args: { username } }, ({ username }) => {
-        cy.get('[data-cy="username"]').type(username)
-        cy.get('[data-cy="login"]').click()
-      })
-
-      cy.document().its('cookie').should('include', `user=${username}`)
-    })
-
     it('handles browser-sent cookies being overridden by server-kept cookies', () => {
       cy.visit('https://localhost:3502/fixtures/primary-origin.html')
       cy.get('[data-cy="cookie-login-override"]').click()
@@ -421,10 +415,10 @@ describe('cy.origin - cookie login', () => {
       username = getUsername()
 
       cy.visit('/fixtures/primary-origin.html')
-      cy.get('[data-cy="cookie-login"]').click()
     })
 
     it('expired -> not logged in', () => {
+      cy.get('[data-cy="cookie-login"]').click()
       cy.origin('http://foobar.com:3500', { args: { username } }, ({ username }) => {
         const expires = (new Date()).toUTCString()
 
@@ -437,6 +431,7 @@ describe('cy.origin - cookie login', () => {
     })
 
     it('expired -> not accessible via cy.getCookie()', () => {
+      cy.get('[data-cy="cookie-login"]').click()
       cy.origin('http://foobar.com:3500', { args: { username } }, ({ username }) => {
         const expires = (new Date()).toUTCString()
 
@@ -449,6 +444,7 @@ describe('cy.origin - cookie login', () => {
     })
 
     it('expired -> not accessible via document.cookie', () => {
+      cy.get('[data-cy="cookie-login-land-on-idp"]').click()
       cy.origin('http://foobar.com:3500', { args: { username } }, ({ username }) => {
         const expires = (new Date()).toUTCString()
 
@@ -457,7 +453,10 @@ describe('cy.origin - cookie login', () => {
         cy.get('[data-cy="login"]').click()
       })
 
-      cy.document().its('cookie').should('not.include', 'user=')
+      cy.origin('http://idp.com:3500', () => {
+        cy.clearCookie('user')
+        cy.document().its('cookie').should('not.include', 'user=')
+      })
     })
   })
 
@@ -468,10 +467,10 @@ describe('cy.origin - cookie login', () => {
       username = getUsername()
 
       cy.visit('/fixtures/primary-origin.html')
-      cy.get('[data-cy="cookie-login"]').click()
     })
 
     it('past max-age -> not logged in', () => {
+      cy.get('[data-cy="cookie-login"]').click()
       cy.origin('http://foobar.com:3500', { args: { username } }, ({ username }) => {
         cy.get('[data-cy="username"]').type(username)
         cy.get('[data-cy="localhostCookieProps"]').type('Max-Age=1')
@@ -487,6 +486,7 @@ describe('cy.origin - cookie login', () => {
     // in Firefox. this issue doesn't seem to be specific to cross-origin tests,
     // as it happens even using cy.setCookie()
     it('past max-age -> not accessible via cy.getCookie()', { browser: '!firefox' }, () => {
+      cy.get('[data-cy="cookie-login"]').click()
       cy.origin('http://foobar.com:3500', { args: { username } }, ({ username }) => {
         cy.get('[data-cy="username"]').type(username)
         cy.get('[data-cy="localhostCookieProps"]').type('Max-Age=1')
@@ -499,18 +499,25 @@ describe('cy.origin - cookie login', () => {
     })
 
     it('past max-age -> not accessible via document.cookie', () => {
+      cy.get('[data-cy="cookie-login-land-on-idp"]').click()
       cy.origin('http://foobar.com:3500', { args: { username } }, ({ username }) => {
         cy.get('[data-cy="username"]').type(username)
         cy.get('[data-cy="localhostCookieProps"]').type('Max-Age=1')
         cy.get('[data-cy="login"]').click()
       })
 
-      cy.wait(1000) // give cookie time to expire
-      cy.reload()
-      cy.document().its('cookie').should('not.include', 'user=')
+      cy.origin('http://idp.com:3500', () => {
+        cy.wait(1000) // give cookie time to expire
+        cy.reload()
+        cy.document().its('cookie').should('not.include', 'user=')
+      })
     })
 
     describe('preference over Expires', () => {
+      beforeEach(() => {
+        cy.get('[data-cy="cookie-login"]').click()
+      })
+
       it('past Max-Age, before Expires -> not logged in', () => {
         const expires = dayjs().add(1, 'day').toDate().toUTCString()
 
@@ -642,4 +649,152 @@ describe('cy.origin - cookie login', () => {
       verifyIdpNotLoggedIn({ isHttps: true, cookieKey: '__Secure-user' })
     })
   })
+
+  describe('document.cookie', () => {
+    let username
+
+    beforeEach(() => {
+      username = getUsername()
+
+      cy.visit('/fixtures/primary-origin.html')
+    })
+
+    it('gets cookie set by http request', () => {
+      cy.get('[data-cy="cookie-login-land-on-idp"]').click()
+      cy.origin('http://foobar.com:3500', { args: { username } }, ({ username }) => {
+        cy.get('[data-cy="username"]').type(username)
+        cy.get('[data-cy="login"]').click()
+      })
+
+      cy.origin('http://idp.com:3500', { args: { username } }, ({ username }) => {
+        cy.document().its('cookie').should('include', `user=${username}`)
+      })
+    })
+
+    it('works when setting cookie', () => {
+      cy.get('[data-cy="cross-origin-secondary-link"]').click()
+      cy.origin('http://foobar.com:3500', () => {
+        cy.document().then((doc) => {
+          doc.cookie = 'key=value'
+        })
+
+        cy.document().its('cookie').should('equal', 'key=value')
+      })
+    })
+
+    it('works when setting cookie with extra, benign parts', () => {
+      cy.get('[data-cy="cross-origin-secondary-link"]').click()
+      cy.origin('http://foobar.com:3500', () => {
+        cy.document().then((doc) => {
+          doc.cookie = 'key=value; wont=beset'
+        })
+
+        cy.document().its('cookie').should('equal', 'key=value')
+      })
+    })
+
+    it('cookie properties are preserved when set via automation', () => {
+      cy.get('[data-cy="cross-origin-secondary-link"]').click()
+      cy.origin('http://foobar.com:3500', () => {
+        cy.document().then((doc) => {
+          doc.cookie = 'key=value; SameSite=Strict; Path=/foo'
+        })
+
+        cy.getCookie('key').then((cookie) => {
+          expect(Cypress._.omit(cookie, 'expiry')).to.deep.equal({
+            domain: '.foobar.com',
+            httpOnly: false,
+            name: 'key',
+            path: '/foo',
+            sameSite: 'strict',
+            secure: false,
+            value: 'value',
+          })
+        })
+      })
+    })
+
+    it('does not set cookie when invalid', () => {
+      cy.get('[data-cy="cross-origin-secondary-link"]').click()
+      cy.origin('http://foobar.com:3500', () => {
+        cy.document().then((doc) => {
+          doc.cookie = '=value'
+        })
+
+        cy.document().its('cookie').should('equal', '')
+      })
+    })
+
+    it('works when setting subsequent cookies', () => {
+      cy.get('[data-cy="cross-origin-secondary-link"]').click()
+      cy.origin('http://foobar.com:3500', () => {
+        cy.document().then((doc) => {
+          doc.cookie = 'key1=value1'
+        })
+
+        cy.document().its('cookie').should('equal', 'key1=value1')
+        cy.document().then((doc) => {
+          doc.cookie = 'key2=value2'
+        })
+
+        cy.document().its('cookie').should('equal', 'key2=value2; key1=value1')
+      })
+    })
+
+    it('makes cookie available to cy.getCookie()', () => {
+      cy.get('[data-cy="cross-origin-secondary-link"]').click()
+      cy.origin('http://foobar.com:3500', () => {
+        cy.document().then((doc) => {
+          doc.cookie = 'key=value'
+        })
+
+        cy.getCookie('key').its('value').should('equal', 'value')
+      })
+    })
+
+    it('no longer returns cookie after cy.clearCookie()', () => {
+      cy.get('[data-cy="cookie-login-land-on-idp"]').click()
+      cy.origin('http://foobar.com:3500', { args: { username } }, ({ username }) => {
+        cy.get('[data-cy="username"]').type(username)
+        cy.get('[data-cy="login"]').click()
+      })
+
+      cy.origin('http://idp.com:3500', () => {
+        cy.clearCookie('user')
+        cy.document().its('cookie').should('equal', '')
+      })
+    })
+
+    it('no longer returns cookie after cy.clearCookies()', () => {
+      cy.get('[data-cy="cookie-login-land-on-idp"]').click()
+      cy.origin('http://foobar.com:3500', { args: { username } }, ({ username }) => {
+        cy.get('[data-cy="username"]').type(username)
+        cy.get('[data-cy="login"]').click()
+      })
+
+      cy.origin('http://idp.com:3500', () => {
+        cy.clearCookies()
+        cy.document().its('cookie').should('equal', '')
+      })
+    })
+
+    it('works when setting cookie in addition to cookie that already exists from http request', () => {
+      cy.get('[data-cy="cookie-login-land-on-idp"]').click()
+      cy.origin('http://foobar.com:3500', { args: { username } }, ({ username }) => {
+        cy.get('[data-cy="username"]').type(username)
+        cy.get('[data-cy="login"]').click()
+      })
+
+      cy.origin('http://idp.com:3500', { args: { username } }, ({ username }) => {
+        cy.document().then((doc) => {
+          doc.cookie = 'key=value'
+        })
+
+        // order of the cookies differs depending on browser, so just
+        // ensure that each one is there
+        cy.document().its('cookie').should('include', 'key=value')
+        cy.document().its('cookie').should('include', `user=${username}`)
+      })
+    })
+  })
 })
diff --git a/packages/driver/cypress/fixtures/primary-origin.html b/packages/driver/cypress/fixtures/primary-origin.html
index b6f06dc0f666..ba33a6f66d38 100644
--- a/packages/driver/cypress/fixtures/primary-origin.html
+++ b/packages/driver/cypress/fixtures/primary-origin.html
@@ -18,14 +18,28 @@
     <li><a data-cy="cookie-login-subdomain">Login with Social (subdomain)</a></li>
     <li><a data-cy="cookie-login-alias">Login with Social (aliased localhost)</a></li>
     <li><a data-cy="cookie-login-override">Login with Social (cookie override)</a></li>
-    <li><a data-cy="welcome" href="http://localhost:3500/welcome">Go to Welcome</a></li>
+    <li><a data-cy="cookie-login-land-on-idp">Login with Social (lands on idp)</a></li>
   </ul>
   <script>
-    document.querySelector('[data-cy=cookie-login]').href = `http://localhost:3500/prelogin?redirect=${encodeURIComponent('http://www.foobar.com:3500/fixtures/auth/cookie-login.html?redirect=http://localhost:3500/login')}`
-    document.querySelector('[data-cy=cookie-login-https]').href = `https://localhost:3502/prelogin?redirect=${encodeURIComponent('https://www.foobar.com:3502/fixtures/auth/cookie-login.html?redirect=https://localhost:3502/login')}`
-    document.querySelector('[data-cy=cookie-login-subdomain]').href = `http://localhost:3500/prelogin?redirect=${encodeURIComponent('http://www.foobar.com:3500/fixtures/auth/cookie-login.html?redirect=http://localhost:3500/login&subdomain=true')}`
-    document.querySelector('[data-cy=cookie-login-alias]').href = `http://localhost:3500/prelogin?redirect=${encodeURIComponent('http://www.foobar.com:3500/fixtures/auth/cookie-login.html?redirect=http://localhost:3500/login&alias=true')}`
-    document.querySelector('[data-cy=cookie-login-override]').href = `https://localhost:3502/prelogin?override=true&redirect=${encodeURIComponent('https://www.foobar.com:3502/fixtures/auth/cookie-login.html?redirect=https://localhost:3502/login')}`
+    function setHref (dataCy, redirect2, primaryQueryAddition = '') {
+      const isHttps = redirect2.startsWith('https')
+      const url = isHttps ? 'https://localhost:3502' : 'http://localhost:3500'
+      const redirect1Path = '/fixtures/auth/cookie-login.html'
+      const redirect = encodeURIComponent(isHttps
+        ? `https://www.foobar.com:3502${redirect1Path}?redirect=${redirect2}`
+        : `http://www.foobar.com:3500${redirect1Path}?redirect=${redirect2}`)
+
+      document.querySelector(`[data-cy="${dataCy}"]`).href = (
+        `${url}/prelogin?redirect=${redirect}${primaryQueryAddition}`
+      )
+    }
+
+    setHref('cookie-login', 'http://localhost:3500/login')
+    setHref('cookie-login-https', 'https://localhost:3502/login')
+    setHref('cookie-login-subdomain', 'http://localhost:3500/login&subdomain=true')
+    setHref('cookie-login-alias', 'http://localhost:3500/login&alias=true')
+    setHref('cookie-login-override', 'https://localhost:3502/login', '&override=true')
+    setHref('cookie-login-land-on-idp', 'http://www.idp.com:3500/welcome')
   </script>
 </body>
 </html>
diff --git a/packages/driver/src/cypress/cookies.ts b/packages/driver/src/cypress/cookies.ts
index 61815680e06c..49d9bc3cee06 100644
--- a/packages/driver/src/cypress/cookies.ts
+++ b/packages/driver/src/cypress/cookies.ts
@@ -1,5 +1,6 @@
 import _ from 'lodash'
 import Cookies from 'js-cookie'
+import { CookieJar, toughCookieToAutomationCookie } from '@packages/server/lib/util/cookies'
 
 import $errUtils from './error_utils'
 
@@ -149,6 +150,11 @@ export const $Cookies = (namespace, domain) => {
       return _.extend(defaults, obj)
     },
 
+    parse (cookieString: string) {
+      return CookieJar.parse(cookieString)
+    },
+
+    toughCookieToAutomationCookie,
   }
 
   return API
diff --git a/packages/proxy/lib/http/index.ts b/packages/proxy/lib/http/index.ts
index 97b6add166c9..7263e2bba2bc 100644
--- a/packages/proxy/lib/http/index.ts
+++ b/packages/proxy/lib/http/index.ts
@@ -20,7 +20,7 @@ import RequestMiddleware from './request-middleware'
 import ResponseMiddleware from './response-middleware'
 import { DeferredSourceMapCache } from '@packages/rewriter'
 import type { RemoteStates } from '@packages/server/lib/remote_states'
-import type { CookieJar } from '@packages/server/lib/cookie-jar'
+import type { CookieJar } from '@packages/server/lib/util/cookies'
 import type { Automation } from '@packages/server/lib/automation/automation'
 
 function getRandomColorFn () {
diff --git a/packages/proxy/lib/http/util/cookies.ts b/packages/proxy/lib/http/util/cookies.ts
index 21fbf78c43dc..1567f5a2028e 100644
--- a/packages/proxy/lib/http/util/cookies.ts
+++ b/packages/proxy/lib/http/util/cookies.ts
@@ -2,8 +2,7 @@ import _ from 'lodash'
 import type Debug from 'debug'
 import { URL } from 'url'
 import { cors } from '@packages/network'
-import { Cookie, CookieJar } from '@packages/server/lib/cookie-jar'
-import type { AutomationCookie } from '@packages/server/lib/automation/cookies'
+import { AutomationCookie, Cookie, CookieJar, toughCookieToAutomationCookie } from '@packages/server/lib/util/cookies'
 
 interface RequestDetails {
   url: string
@@ -32,26 +31,6 @@ export const getSameSiteContext = (autUrl: string | undefined, requestUrl: strin
   return isAUTFrameRequest ? 'lax' : 'none'
 }
 
-const sameSiteNoneRe = /; +samesite=(?:'none'|"none"|none)/i
-
-export const parseCookie = (cookie: string) => {
-  const toughCookie = CookieJar.parse(cookie)
-
-  if (!toughCookie) return
-
-  // fixes tough-cookie defaulting undefined/invalid SameSite to 'none'
-  // https://github.com/salesforce/tough-cookie/issues/191
-  const hasUnspecifiedSameSite = toughCookie.sameSite === 'none' && !sameSiteNoneRe.test(cookie)
-
-  // not all browsers currently default to lax, but they're heading in that
-  // direction since it's now the standard, so this is more future-proof
-  if (hasUnspecifiedSameSite) {
-    toughCookie.sameSite = 'lax'
-  }
-
-  return toughCookie
-}
-
 const comparableCookieString = (toughCookie: Cookie): string => {
   return _(toughCookie)
   .pick('key', 'value', 'domain', 'path')
@@ -71,22 +50,6 @@ const matchesPreviousCookie = (previousCookies: Cookie[], cookie: Cookie) => {
   })
 }
 
-const toughCookieToAutomationCookie = (toughCookie: Cookie, defaultDomain: string): AutomationCookie => {
-  const expiry = toughCookie.expiryTime()
-
-  return {
-    domain: toughCookie.domain || defaultDomain,
-    expiry: isFinite(expiry) ? expiry / 1000 : null,
-    httpOnly: toughCookie.httpOnly,
-    maxAge: toughCookie.maxAge,
-    name: toughCookie.key,
-    path: toughCookie.path,
-    sameSite: toughCookie.sameSite === 'none' ? 'no_restriction' : toughCookie.sameSite,
-    secure: toughCookie.secure,
-    value: toughCookie.value,
-  }
-}
-
 /**
  * Utility for dealing with cross-origin cookies
  * - Tracks which cookies were added to our server-side cookie jar during
@@ -140,7 +103,7 @@ export class CookiesHelper {
   }
 
   setCookie (cookie: string) {
-    const toughCookie = parseCookie(cookie)
+    const toughCookie = CookieJar.parse(cookie)
 
     // don't set the cookie in our own cookie jar if the parsed cookie is
     // undefined (meaning it's invalid) or if the browser would not set it
diff --git a/packages/runner/injection/cookies.js b/packages/runner/injection/cookies.js
new file mode 100644
index 000000000000..fcad09e0dc05
--- /dev/null
+++ b/packages/runner/injection/cookies.js
@@ -0,0 +1,82 @@
+/* global document */
+
+// document.cookie monkey-patching
+// -------------------------------
+// We monkey-patch document.cookie when in a cross-origin injection, because
+// document.cookie runs into cross-origin restrictions when the AUT is on
+// a different origin than top. The goal is to make it act like it would
+// if the user's app was run in top.
+//
+// The general strategy is:
+// - Keep the document.cookie value (`documentCookieValue`) available so
+//   the document.cookie getter can synchronously return it.
+// - Optimistically update that value when document.cookie is set, so that
+//   subsequent synchronous calls to get the value will work.
+// - On an interval, get the browser's cookies for the given domain, so that
+//   updates to the cookie jar (via http requests, cy.setCookie, etc) are
+//   reflected in the document.cookie value.
+export const patchDocumentCookie = (Cypress) => {
+  const setAutomationCookie = (toughCookie) => {
+    const { superDomain } = Cypress.Location.create(window.location.href)
+    const automationCookie = Cypress.Cookies.toughCookieToAutomationCookie(toughCookie, superDomain)
+
+    Cypress.automation('set:cookie', automationCookie)
+    .catch(() => {
+      // unlikely there will be errors, but ignore them in any case, since
+      // they're not user-actionable
+    })
+  }
+
+  let documentCookieValue = ''
+
+  Object.defineProperty(document, 'cookie', {
+    get () {
+      return documentCookieValue
+    },
+
+    set (newValue) {
+      const cookie = Cypress.Cookies.parse(newValue)
+
+      // If cookie is undefined, it was invalid and couldn't be parsed
+      if (!cookie) return documentCookieValue
+
+      const cookieString = `${cookie.key}=${cookie.value}`
+
+      // New cookies get prepended to existing cookies
+      documentCookieValue = documentCookieValue.length
+        ? `${cookieString}; ${documentCookieValue}`
+        : cookieString
+
+      setAutomationCookie(cookie)
+
+      return documentCookieValue
+    },
+  })
+
+  // The interval value is arbitrary; it shouldn't be too often, but needs to
+  // be fairly frequent so that the local value is kept as up-to-date as
+  // possible. It's possible there could be a race condition where
+  // document.cookie returns an out-of-date value, but there's not really a
+  // way around that since it's a synchronous API and we can only get the
+  // browser's true cookie values asynchronously.
+  const intervalId = setInterval(async () => {
+    const { superDomain: domain } = Cypress.Location.create(window.location.href)
+
+    try {
+      const cookies = await Cypress.automation('get:cookies', { domain })
+      const cookiesString = (cookies || []).map((c) => `${c.name}=${c.value}`).join('; ')
+
+      documentCookieValue = cookiesString
+    } catch (err) {
+      // unlikely there will be errors, but ignore them in any case, since
+      // they're not user-actionable
+    }
+  }, 250)
+
+  const onUnload = () => {
+    window.removeEventListener('unload', onUnload)
+    clearInterval(intervalId)
+  }
+
+  window.addEventListener('unload', onUnload)
+}
diff --git a/packages/runner/injection/cross-origin.js b/packages/runner/injection/cross-origin.js
index 316752571a2f..9470e4ad20e4 100644
--- a/packages/runner/injection/cross-origin.js
+++ b/packages/runner/injection/cross-origin.js
@@ -8,6 +8,7 @@
  */
 
 import { createTimers } from './timers'
+import { patchDocumentCookie } from './cookies'
 
 const findCypress = () => {
   for (let index = 0; index < window.parent.frames.length; index++) {
@@ -40,6 +41,8 @@ const findCypress = () => {
 
 const Cypress = findCypress()
 
+patchDocumentCookie(Cypress)
+
 // the timers are wrapped in the injection code similar to the primary origin
 const timers = createTimers()
 
diff --git a/packages/server/lib/automation/automation.ts b/packages/server/lib/automation/automation.ts
index ac7317348e8e..1f22001d7c83 100644
--- a/packages/server/lib/automation/automation.ts
+++ b/packages/server/lib/automation/automation.ts
@@ -4,7 +4,7 @@ import { Cookies } from './cookies'
 import { Screenshot } from './screenshot'
 import type { BrowserPreRequest } from '@packages/proxy'
 import type { AutomationMiddleware, OnRequestEvent } from '@packages/types'
-import { cookieJar } from '../cookie-jar'
+import { cookieJar } from '../util/cookies'
 
 export type OnBrowserPreRequest = (browserPreRequest: BrowserPreRequest) => void
 
diff --git a/packages/server/lib/open_project.ts b/packages/server/lib/open_project.ts
index 1cd7bf3c564a..fb562e5ee97d 100644
--- a/packages/server/lib/open_project.ts
+++ b/packages/server/lib/open_project.ts
@@ -10,7 +10,7 @@ import * as errors from './errors'
 import preprocessor from './plugins/preprocessor'
 import runEvents from './plugins/run_events'
 import * as session from './session'
-import { cookieJar } from './cookie-jar'
+import { cookieJar } from './util/cookies'
 import { getSpecUrl } from './project_utils'
 import type { LaunchOpts, OpenProjectLaunchOptions, InitializeProjectOptions } from '@packages/types'
 import { DataContext, getCtx } from '@packages/data-context'
diff --git a/packages/server/lib/server-base.ts b/packages/server/lib/server-base.ts
index 4c2fa9ec49e4..2957f79e9858 100644
--- a/packages/server/lib/server-base.ts
+++ b/packages/server/lib/server-base.ts
@@ -32,7 +32,7 @@ import { createRoutesCT } from './routes-ct'
 import type { FoundSpec } from '@packages/types'
 import type { Server as WebSocketServer } from 'ws'
 import { RemoteStates } from './remote_states'
-import { cookieJar } from './cookie-jar'
+import { cookieJar } from './util/cookies'
 import type { Automation } from './automation/automation'
 import type { AutomationCookie } from './automation/cookies'
 
diff --git a/packages/server/lib/socket-base.ts b/packages/server/lib/socket-base.ts
index 259d8b579df0..c88e918c5eb0 100644
--- a/packages/server/lib/socket-base.ts
+++ b/packages/server/lib/socket-base.ts
@@ -16,7 +16,7 @@ import { openFile, OpenFileDetails } from './util/file-opener'
 import open from './util/open'
 import type { DestroyableHttpServer } from './util/server_destroy'
 import * as session from './session'
-import { cookieJar } from './cookie-jar'
+import { cookieJar } from './util/cookies'
 // eslint-disable-next-line no-duplicate-imports
 import type { Socket } from '@packages/socket'
 import path from 'path'
diff --git a/packages/server/lib/cookie-jar.ts b/packages/server/lib/util/cookies.ts
similarity index 54%
rename from packages/server/lib/cookie-jar.ts
rename to packages/server/lib/util/cookies.ts
index 70631035135a..0dce02e47838 100644
--- a/packages/server/lib/cookie-jar.ts
+++ b/packages/server/lib/util/cookies.ts
@@ -1,6 +1,7 @@
 import { Cookie, CookieJar as ToughCookieJar } from 'tough-cookie'
+import type { AutomationCookie } from '../automation/cookies'
 
-export { Cookie }
+export { AutomationCookie, Cookie }
 
 interface CookieData {
   name: string
@@ -8,6 +9,24 @@ interface CookieData {
   path?: string
 }
 
+export const toughCookieToAutomationCookie = (toughCookie: Cookie, defaultDomain: string): AutomationCookie => {
+  const expiry = toughCookie.expiryTime()
+
+  return {
+    domain: toughCookie.domain || defaultDomain,
+    expiry: isFinite(expiry) ? expiry / 1000 : null,
+    httpOnly: toughCookie.httpOnly,
+    maxAge: toughCookie.maxAge,
+    name: toughCookie.key,
+    path: toughCookie.path,
+    sameSite: toughCookie.sameSite === 'none' ? 'no_restriction' : toughCookie.sameSite,
+    secure: toughCookie.secure,
+    value: toughCookie.value,
+  }
+}
+
+const sameSiteNoneRe = /; +samesite=(?:'none'|"none"|none)/i
+
 /**
  * An adapter for tough-cookie's CookieJar
  * Holds onto cookies captured via the proxy, so they can be applied to
@@ -16,8 +35,22 @@ interface CookieData {
 export class CookieJar {
   _cookieJar: ToughCookieJar
 
-  static parse (cookie) {
-    return Cookie.parse(cookie)
+  static parse (cookie: string) {
+    const toughCookie = Cookie.parse(cookie)
+
+    if (!toughCookie) return
+
+    // fixes tough-cookie defaulting undefined/invalid SameSite to 'none'
+    // https://github.com/salesforce/tough-cookie/issues/191
+    const hasUnspecifiedSameSite = toughCookie.sameSite === 'none' && !sameSiteNoneRe.test(cookie)
+
+    // not all browsers currently default to lax, but they're heading in that
+    // direction since it's now the standard, so this is more future-proof
+    if (hasUnspecifiedSameSite) {
+      toughCookie.sameSite = 'lax'
+    }
+
+    return toughCookie
   }
 
   constructor () {