diff --git a/e2e/cypress/integration/dashboard-xhr.spec.ts b/e2e/cypress/integration/dashboard-xhr.spec.ts
index 4a093c517a..9cb0752f35 100644
--- a/e2e/cypress/integration/dashboard-xhr.spec.ts
+++ b/e2e/cypress/integration/dashboard-xhr.spec.ts
@@ -1,5 +1,6 @@
 import {
   interceptCompanionUrlMetaRequest,
+  interceptCompanionUrlRequest,
   runRemoteUrlImageUploadTest,
   runRemoteUnsplashUploadTest,
 } from './reusable-tests.ts'
@@ -57,6 +58,17 @@ describe('Dashboard with XHR', () => {
     })
   })
 
+  it('should upload unknown size files', () => {
+    cy.get('[data-cy="Url"]').click()
+    cy.get('.uppy-Url-input').type('http://localhost:4678/unknown-size')
+    cy.get('.uppy-Url-importButton').click()
+    interceptCompanionUrlRequest()
+    cy.get('.uppy-StatusBar-actionBtn--upload').click()
+    cy.wait('@url').then(() => {
+      cy.get('.uppy-StatusBar-statusPrimary').should('contain', 'Complete')
+    })
+  })
+
   it('should upload remote image with Unsplash plugin', () => {
     runRemoteUnsplashUploadTest()
   })
diff --git a/e2e/cypress/integration/reusable-tests.ts b/e2e/cypress/integration/reusable-tests.ts
index d311b60e39..39031d8281 100644
--- a/e2e/cypress/integration/reusable-tests.ts
+++ b/e2e/cypress/integration/reusable-tests.ts
@@ -1,6 +1,6 @@
 /* global cy */
 
-const interceptCompanionUrlRequest = () =>
+export const interceptCompanionUrlRequest = () =>
   cy
     .intercept({ method: 'POST', url: 'http://localhost:3020/url/get' })
     .as('url')
diff --git a/e2e/mock-server.mjs b/e2e/mock-server.mjs
index 02d84b77da..6678de6ff8 100644
--- a/e2e/mock-server.mjs
+++ b/e2e/mock-server.mjs
@@ -13,6 +13,31 @@ const requestListener = (req, res) => {
     }
     case '/file-no-headers':
       break
+    
+    case '/unknown-size': {
+      res.setHeader('Content-Type', 'text/html; charset=UTF-8');
+      res.setHeader('Transfer-Encoding', 'chunked');
+      const chunkSize = 1e5;
+      if (req.method === 'GET') {
+        let i = 0;
+        const interval = setInterval(() => {
+          if (i >= 10) { // 1MB
+            clearInterval(interval);
+            res.end();
+            return;
+          }
+          res.write(Buffer.from(Array.from({ length: chunkSize }, () => '1').join('')));
+          res.write('\n');
+          i++;
+        }, 10);
+      } else if (req.method === 'HEAD') {
+        res.end();
+      } else {
+        throw new Error('Unhandled method')
+      }
+    }
+    break;
+    
     default:
       res.writeHead(404).end('Unhandled request')
   }