diff --git a/ghost/core/playwright.config.js b/ghost/core/playwright.config.js
index 612bf77922..3152fbc010 100644
--- a/ghost/core/playwright.config.js
+++ b/ghost/core/playwright.config.js
@@ -5,6 +5,7 @@ const config = {
     expect: {
         timeout: 10000
     },
+    workers: process.env.CI ? '100%' : (process.env.PLAYWRIGHT_SLOWMO ? 1 : undefined),
     reporter: [['list', {printSteps: true}]],
     use: {
         // Use a single browser since we can't simultaneously test multiple browsers
diff --git a/ghost/core/test/e2e-browser/portal/offers.spec.js b/ghost/core/test/e2e-browser/portal/offers.spec.js
index 6b5aa613e7..7b59df3159 100644
--- a/ghost/core/test/e2e-browser/portal/offers.spec.js
+++ b/ghost/core/test/e2e-browser/portal/offers.spec.js
@@ -137,7 +137,7 @@ test.describe('Portal', () => {
             await page.locator('.gh-nav a[href="#/members/"]').click();
 
             // 1 member, should be Testy, on Portal Tier
-            await expect(page.getByRole('link', {name: 'Testy McTesterson example.com'}), 'Should have 1 paid member').toBeVisible();
+            await expect(page.getByRole('link', {name: 'Testy McTesterson testy@example.com'}), 'Should have 1 paid member').toBeVisible();
             await expect(page.getByRole('link', {name: tierName}), `Paid member should be on ${tierName}`).toBeVisible();
         });
 
diff --git a/ghost/core/test/e2e-browser/portal/upgrade.spec.js b/ghost/core/test/e2e-browser/portal/upgrade.spec.js
index 9f67127c43..9e5ba7303e 100644
--- a/ghost/core/test/e2e-browser/portal/upgrade.spec.js
+++ b/ghost/core/test/e2e-browser/portal/upgrade.spec.js
@@ -54,6 +54,9 @@ test.describe('Portal', () => {
     });
 
     test.describe('Upgrade: Single Tier', () => {
+        // Because memberUrl is set during first test, we need to run these tests in series
+        test.describe.configure({mode: 'serial'});
+
         let memberUrl;
         const tierName = 'The Local Test';
         const member = {