diff --git a/packages/service-worker/worker/src/driver.ts b/packages/service-worker/worker/src/driver.ts
index 9ff50cfc75fef..186f21ed80f17 100644
--- a/packages/service-worker/worker/src/driver.ts
+++ b/packages/service-worker/worker/src/driver.ts
@@ -176,11 +176,12 @@ export class Driver implements Debuggable, UpdateSource {
    */
   private onFetch(event: FetchEvent): void {
     const req = event.request;
+    const scopeUrl = this.scope.registration.scope;
+    const requestUrlObj = this.adapter.parseUrl(req.url, scopeUrl);
 
     // The only thing that is served unconditionally is the debug page.
-    if (this.adapter.parseUrl(req.url, this.scope.registration.scope).path === '/ngsw/state') {
-      // Allow the debugger to handle the request, but don't affect SW state in any
-      // other way.
+    if (requestUrlObj.path === '/ngsw/state') {
+      // Allow the debugger to handle the request, but don't affect SW state in any other way.
       event.respondWith(this.debugger.handleFetch(req));
       return;
     }
@@ -197,6 +198,16 @@ export class Driver implements Debuggable, UpdateSource {
       return;
     }
 
+    // Although "passive mixed content" (like images) only produces a warning without a
+    // ServiceWorker, fetching it via a ServiceWorker results in an error. Let such requests be
+    // handled by the browser, since handling with the ServiceWorker would fail anyway.
+    // See https://github.com/angular/angular/issues/23012#issuecomment-376430187 for more details.
+    if (requestUrlObj.origin.startsWith('http:') && scopeUrl.startsWith('https:')) {
+      // Still, log the incident for debugging purposes.
+      this.debugger.log(`Ignoring passive mixed content request: Driver.fetch(${req.url})`);
+      return;
+    }
+
     // When opening DevTools in Chrome, a request is made for the current URL (and possibly related
     // resources, e.g. scripts) with `cache: 'only-if-cached'` and `mode: 'no-cors'`. These request
     // will eventually fail, because `only-if-cached` is only allowed to be used with
@@ -204,7 +215,7 @@ export class Driver implements Debuggable, UpdateSource {
     // This is likely a bug in Chrome DevTools. Avoid handling such requests.
     // (See also https://github.com/angular/angular/issues/22362.)
     // TODO(gkalpak): Remove once no longer necessary (i.e. fixed in Chrome DevTools).
-    if ((req.cache as string) === 'only-if-cached' && req.mode !== 'same-origin') {
+    if (req.cache === 'only-if-cached' && req.mode !== 'same-origin') {
       // Log the incident only the first time it happens, to avoid spamming the logs.
       if (!this.loggedInvalidOnlyIfCachedRequest) {
         this.loggedInvalidOnlyIfCachedRequest = true;
diff --git a/packages/service-worker/worker/test/happy_spec.ts b/packages/service-worker/worker/test/happy_spec.ts
index a4fba8680a4fe..783b3a8cfe03c 100644
--- a/packages/service-worker/worker/test/happy_spec.ts
+++ b/packages/service-worker/worker/test/happy_spec.ts
@@ -204,8 +204,6 @@ const brokenServer =
 
 const server404 = new MockServerStateBuilder().withStaticFiles(dist).build();
 
-const scope = new SwTestHarnessBuilder().withServerState(server).build();
-
 const manifestHash = sha1(JSON.stringify(manifest));
 const manifestUpdateHash = sha1(JSON.stringify(manifestUpdate));
 
@@ -1008,6 +1006,38 @@ const manifestUpdateHash = sha1(JSON.stringify(manifestUpdate));
         expect(await requestFoo('only-if-cached', 'no-cors')).toBeNull();
       });
 
+      async_it('ignores passive mixed content requests ', async() => {
+        const scopeFetchSpy = spyOn(scope, 'fetch').and.callThrough();
+        const getRequestUrls = () => scopeFetchSpy.calls.allArgs().map(args => args[0].url);
+
+        const httpScopeUrl = 'http://mock.origin.dev';
+        const httpsScopeUrl = 'https://mock.origin.dev';
+        const httpRequestUrl = 'http://other.origin.sh/unknown.png';
+        const httpsRequestUrl = 'https://other.origin.sh/unknown.pnp';
+
+        // Registration scope: `http:`
+        (scope.registration.scope as string) = httpScopeUrl;
+
+        await makeRequest(scope, httpRequestUrl);
+        await makeRequest(scope, httpsRequestUrl);
+        const requestUrls1 = getRequestUrls();
+
+        expect(requestUrls1).toContain(httpRequestUrl);
+        expect(requestUrls1).toContain(httpsRequestUrl);
+
+        scopeFetchSpy.calls.reset();
+
+        // Registration scope: `https:`
+        (scope.registration.scope as string) = httpsScopeUrl;
+
+        await makeRequest(scope, httpRequestUrl);
+        await makeRequest(scope, httpsRequestUrl);
+        const requestUrls2 = getRequestUrls();
+
+        expect(requestUrls2).not.toContain(httpRequestUrl);
+        expect(requestUrls2).toContain(httpsRequestUrl);
+      });
+
       describe('Backwards compatibility with v5', () => {
         beforeEach(() => {
           const serverV5 = new MockServerStateBuilder()
diff --git a/packages/service-worker/worker/testing/scope.ts b/packages/service-worker/worker/testing/scope.ts
index 5262257800551..6b5127d947505 100644
--- a/packages/service-worker/worker/testing/scope.ts
+++ b/packages/service-worker/worker/testing/scope.ts
@@ -181,7 +181,7 @@ export class SwTestHarness implements ServiceWorkerGlobalScope, Adapter, Context
       return {origin: obj.origin, path: obj.pathname};
     } else {
       const obj = require('url').parse(url);
-      return {origin: obj.origin, path: obj.pathname};
+      return {origin: `${obj.protocol}//${obj.host}`, path: obj.pathname};
     }
   }