diff --git a/.github/workflows/CICD.yml b/.github/workflows/CICD.yml
index dcad9c6..83b2644 100644
--- a/.github/workflows/CICD.yml
+++ b/.github/workflows/CICD.yml
@@ -37,7 +37,8 @@ jobs:
       matrix:
         browser:
           - chrome
-          # - firefox
+          - firefox
+          - edge
         viewport:
           [
             "viewportWidth=375,viewportHeight=667",
@@ -61,7 +62,7 @@ jobs:
         if: always()
         uses: actions/upload-artifact@v4
         with:
-          name: videos
+          name: videos-${{ matrix.browser }}-${{ strategy.job-index }}
           path: cypress/videos
           retention-days: 5
 
diff --git a/cypress.config.js b/cypress.config.js
index 83460c3..e0a6a58 100644
--- a/cypress.config.js
+++ b/cypress.config.js
@@ -5,5 +5,22 @@ export default defineConfig({
   allowCypressEnv: false,
   e2e: {
     baseUrl: "http://localhost:5173",
+    setupNodeEvents(on, config) {
+      on('before:browser:launch', (browser, launchOptions) => {
+        if (browser.name === 'firefox') {
+          // Firefox doesn't auto-download files; configure it to save
+          // directly to the Cypress downloads folder without prompting.
+          launchOptions.preferences['browser.download.folderList'] = 2;
+          launchOptions.preferences['browser.download.dir'] =
+            config.downloadsFolder;
+          launchOptions.preferences[
+            'browser.helperApps.neverAsk.saveToDisk'
+          ] =
+            'text/csv,application/octet-stream,application/yaml,text/yaml,text/plain,application/x-yaml';
+          launchOptions.preferences['pdfjs.disabled'] = true;
+        }
+        return launchOptions;
+      });
+    },
   },
 });
diff --git a/cypress/e2e/Card.cy.js b/cypress/e2e/Card.cy.js
index 6b74397..5a8c728 100644
--- a/cypress/e2e/Card.cy.js
+++ b/cypress/e2e/Card.cy.js
@@ -15,6 +15,7 @@ context('Card', () => {
       .first()
       .find('[data-name=card-author-input]')
       .type('Test Author{enter}');
+    cy.get('[data-name=card]:visible').should('exist');
   });
 
   beforeEach(() => {
diff --git a/cypress/e2e/ConnectionLost.cy.js b/cypress/e2e/ConnectionLost.cy.js
index a2bae19..5ae8611 100644
--- a/cypress/e2e/ConnectionLost.cy.js
+++ b/cypress/e2e/ConnectionLost.cy.js
@@ -20,6 +20,14 @@ context('ConnectionLost', () => {
     cy.get('[data-name=rank]:visible').should('exist');
   });
 
+  // Firefox keeps navigator.onLine = false across navigations when the
+  // offline event was dispatched programmatically. Restoring online state
+  // here prevents Firebase auth from failing in the next beforeEach or the
+  // after hook.
+  afterEach(() => {
+    cy.window().then((win) => win.dispatchEvent(new Event('online')));
+  });
+
   it('shows a connection lost alert when the browser goes offline', () => {
     cy.window().then((win) => win.dispatchEvent(new Event('offline')));
     cy.get('[data-name=error-alert]').should('be.visible');
@@ -34,6 +42,7 @@ context('ConnectionLost', () => {
   });
 
   after(() => {
+    cy.window().then((win) => win.dispatchEvent(new Event('online')));
     cy.deleteAllBoards();
   });
 });
diff --git a/cypress/e2e/Menu.cy.js b/cypress/e2e/Menu.cy.js
index d24a670..2f9463f 100644
--- a/cypress/e2e/Menu.cy.js
+++ b/cypress/e2e/Menu.cy.js
@@ -183,6 +183,8 @@ context('Menu', () => {
 
   it('csv created_at timestamp is within 24 hours of the current time', () => {
     const cardText = 'Timestamp test card';
+    const date = new Date().toISOString().slice(0, 10);
+    const csvPath = `cypress/downloads/Test Board Name-${date}.csv`;
 
     cy.get('[data-name=rank]:visible')
       .first()
@@ -191,13 +193,12 @@ context('Menu', () => {
       .should('have.value', '');
     cy.get('[data-name=card]:visible').should('exist');
 
+    // Delete any existing file so Firefox doesn't rename the new download.
+    cy.exec(`rm -f "${csvPath}"`);
     cy.get('[data-name=menu-button]').click();
     cy.get('[data-name=download-csv-button]').click();
 
-    const date = new Date().toISOString().slice(0, 10);
-    // Use .should() so Cypress retries readFile until the new download
-    // overwrites a stale CSV from an earlier test in this suite.
-    cy.readFile(`cypress/downloads/Test Board Name-${date}.csv`)
+    cy.readFile(csvPath)
       .should('include', cardText)
       .then((csv) => {
         const [, ...rows] = csv.trim().split('\n');
diff --git a/cypress/e2e/OwnerRealtimeSync.cy.js b/cypress/e2e/OwnerRealtimeSync.cy.js
index f350b5a..de3a2c2 100644
--- a/cypress/e2e/OwnerRealtimeSync.cy.js
+++ b/cypress/e2e/OwnerRealtimeSync.cy.js
@@ -38,21 +38,28 @@ context('OwnerRealtimeSync', () => {
     // Owner loads the board — with the fix, a Firestore subscription is established
     // for owners when open_permission is active
     cy.login('owner');
+    // Capture the session cookie now, before cy.visit() causes the app to call
+    // /auth again. In Firefox, that re-auth can overwrite __session with a new
+    // anonymous-user token that doesn't own the board, causing PATCH → 403.
+    cy.getCookie('__session').as('ownerSession');
     cy.visit(boardUrl);
     cy.get('[data-name=rank]:visible').should('exist');
     cy.get('[data-name=vote-button]:visible').should('exist');
 
     // PATCH the board via REST, bypassing the Svelte store entirely.
     // Only the Firestore subscription — not the local store listener — can deliver this update.
-    cy.request(`/boards/${boardId}`).then(({ body }) => {
-      let data = body.data;
-      try {
-        data = JSON.parse(data);
-      } catch {}
-      cy.request({
-        method: 'PATCH',
-        url: `/boards/${boardId}`,
-        body: { ...body, data, voting_open: false },
+    cy.get('@ownerSession').then((cookie) => {
+      cy.request(`/boards/${boardId}`).then(({ body }) => {
+        let data = body.data;
+        try {
+          data = JSON.parse(data);
+        } catch {}
+        cy.request({
+          method: 'PATCH',
+          url: `/boards/${boardId}`,
+          body: { ...body, data, voting_open: false },
+          headers: { Cookie: `__session=${cookie.value}` },
+        });
       });
     });
 
diff --git a/cypress/e2e/TemplateRoundTrip.cy.js b/cypress/e2e/TemplateRoundTrip.cy.js
index 7a7cb44..a474ca1 100644
--- a/cypress/e2e/TemplateRoundTrip.cy.js
+++ b/cypress/e2e/TemplateRoundTrip.cy.js
@@ -276,10 +276,11 @@ context(
       // Rename the first column — this removes the i18n key from the export
       customiseFirstRank({ name: 'My Custom Column' });
 
+      // Delete the file from the German-export test so Firefox doesn't save
+      // the new download under a deduplicated name (e.g. "file (1).yaml").
+      cy.exec(`rm -f "${DOWNLOAD_FILE}"`);
       downloadTemplate();
 
-      // The file already exists from the German-export test in this context.
-      // Use .should() so Cypress retries readFile until the download overwrites it.
       cy.readFile(DOWNLOAD_FILE)
         .should('include', 'My Custom Column')
         .then((text) => {
diff --git a/cypress/support/e2e.js b/cypress/support/e2e.js
index c5e5951..3140ef0 100644
--- a/cypress/support/e2e.js
+++ b/cypress/support/e2e.js
@@ -1,3 +1,19 @@
+// Firefox aborts in-flight fetch() calls during navigation and surfaces them
+// as "NetworkError when attempting to fetch resource" unhandled rejections.
+// Chrome drops the same aborted requests silently. Returning false here tells
+// Cypress not to fail the test for this browser-specific behaviour.
+Cypress.on('uncaught:exception', (err) => {
+  // Firefox reports aborted fetch calls during navigation as NetworkError.
+  if (err.message.includes('NetworkError when attempting to fetch resource')) {
+    return false;
+  }
+  // Firebase auth can fail with this when the browser is in a simulated
+  // offline state (navigator.onLine = false in Firefox).
+  if (err.message.includes('auth/network-request-failed')) {
+    return false;
+  }
+});
+
 Cypress.Commands.add('login', (name = 'owner') => {
   cy.session(
     name,