diff --git a/experimental/puppeteer-firefox/lib/Page.js b/experimental/puppeteer-firefox/lib/Page.js
index bc733a1bb892e..91c355355d4f6 100644
--- a/experimental/puppeteer-firefox/lib/Page.js
+++ b/experimental/puppeteer-firefox/lib/Page.js
@@ -1,4 +1,4 @@
-const {helper, debugError} = require('./helper');
+const {helper, debugError, assert} = require('./helper');
 const {Keyboard, Mouse} = require('./Input');
 const {Dialog} = require('./Dialog');
 const {TimeoutError} = require('./Errors');
@@ -84,6 +84,14 @@ class Page extends EventEmitter {
     await this._networkManager.setExtraHTTPHeaders(headers);
   }
 
+  /**
+   * @param {?string} mediaType
+   */
+  async emulateMedia(mediaType) {
+    assert(mediaType === 'screen' || mediaType === 'print' || mediaType === null, 'Unsupported media type: ' + mediaType);
+    await this._session.send('Page.setEmulatedMedia', {media: mediaType || ''});
+  }
+
   /**
    * @param {string} name
    * @param {Function} puppeteerFunction
diff --git a/experimental/puppeteer-firefox/package.json b/experimental/puppeteer-firefox/package.json
index ec7d8e9d451e2..08a899694c0d8 100644
--- a/experimental/puppeteer-firefox/package.json
+++ b/experimental/puppeteer-firefox/package.json
@@ -9,7 +9,7 @@
     "node": ">=8.9.4"
   },
   "puppeteer": {
-    "firefox_revision": "f8e2e3a2e86cd47766cd839624b3f08e093c1f27"
+    "firefox_revision": "86e93329fd528bd28ff1493f117f126b6f010eac"
   },
   "scripts": {
     "install": "node install.js",
diff --git a/test/elementhandle.spec.js b/test/elementhandle.spec.js
index 7b3be85fdd8df..3c71650840de2 100644
--- a/test/elementhandle.spec.js
+++ b/test/elementhandle.spec.js
@@ -16,7 +16,7 @@
 
 const utils = require('./utils');
 
-module.exports.addTests = function({testRunner, expect}) {
+module.exports.addTests = function({testRunner, expect, CHROME}) {
   const {describe, xdescribe, fdescribe, describe_fails_ffox} = testRunner;
   const {it, fit, xit, it_fails_ffox} = testRunner;
   const {beforeAll, beforeEach, afterAll, afterEach} = testRunner;
@@ -29,13 +29,16 @@ module.exports.addTests = function({testRunner, expect}) {
       const box = await elementHandle.boundingBox();
       expect(box).toEqual({ x: 100, y: 50, width: 50, height: 50 });
     });
-    it_fails_ffox('should handle nested frames', async({page, server}) => {
+    it('should handle nested frames', async({page, server}) => {
       await page.setViewport({width: 500, height: 500});
       await page.goto(server.PREFIX + '/frames/nested-frames.html');
       const nestedFrame = page.frames()[1].childFrames()[1];
       const elementHandle = await nestedFrame.$('div');
       const box = await elementHandle.boundingBox();
-      expect(box).toEqual({ x: 28, y: 260, width: 264, height: 18 });
+      if (CHROME)
+        expect(box).toEqual({ x: 28, y: 260, width: 264, height: 18 });
+      else
+        expect(box).toEqual({ x: 28, y: 182, width: 254, height: 18 });
     });
     it('should return null for invisible elements', async({page, server}) => {
       await page.setContent('<div style="display:none">hi</div>');
diff --git a/test/emulation.spec.js b/test/emulation.spec.js
index a2ce575f6f939..72a6ad1d5c111 100644
--- a/test/emulation.spec.js
+++ b/test/emulation.spec.js
@@ -99,7 +99,7 @@ module.exports.addTests = function({testRunner, expect, product}) {
     });
   });
 
-  describe_fails_ffox('Page.emulateMedia', function() {
+  describe('Page.emulateMedia', function() {
     it('should work', async({page, server}) => {
       expect(await page.evaluate(() => window.matchMedia('screen').matches)).toBe(true);
       expect(await page.evaluate(() => window.matchMedia('print').matches)).toBe(false);
diff --git a/test/evaluation.spec.js b/test/evaluation.spec.js
index d03b4f5d205bc..ddab30b50fd78 100644
--- a/test/evaluation.spec.js
+++ b/test/evaluation.spec.js
@@ -101,7 +101,7 @@ module.exports.addTests = function({testRunner, expect}) {
       await page.goto(server.EMPTY_PAGE);
       expect(await frameEvaluation).toBe(42);
     });
-    it_fails_ffox('should work from-inside an exposed function', async({page, server}) => {
+    it('should work from-inside an exposed function', async({page, server}) => {
       // Setup inpage callback, which calls Page.evaluate
       await page.exposeFunction('callController', async function(a, b) {
         return await page.evaluate((a, b) => a * b, a, b);