Web-bugs: englishtest.duolingo.com - The Firefox browser is not supported

[webcompat-bot]

URL: https://englishtest.duolingo.com/quick

Browser / Version: Firefox 81.0
Operating System: Windows 10
Tested Another Browser: Yes Chrome

Problem type: Site is not usable
Description: Browser unsupported
Steps to Reproduce:
They require a Chromium browser, Firefox is blocked.

View the screenshot

Browser Configuration

• None

_From webcompat.com with ❤️_

[cipriansv]

Thanks for the report.

I was indeed able to reproduce the issue. The Firefox browser is not supported.

Tested with:
Browser / Version: Firefox Nightly 81.0a1 (2020-08-02), Chrome 84.0.4147.111
Operating System: macOS 10.15.6

This is the web page displayed in Firefox Nightly after deciding to take a practice test:

And this is the web page displayed in Chrome:

Moving the issue to needsdiagnosis.

[karlcow]

    E = function (e) {
      v('_unsupportedBrowser', (function () {
        window.location.href = e ? '/' : '/browsers'
      }), (function () {
        window.location.href = '/'
      }), {
        showMobile: e
      }),
      e && r.f.defer((function () {
        u.$('.supported-browsers-container').html((new s.a).render().el)
      }))

called by

        var a = Ie.a.isMobile();
        if (o.f.contains(this.SUPPORTED_BROWSER_ROUTES, n) && !Ie.a.isSupportedBrowser()) return w.g(a),
        !1;
        if (o.f.contains(this.DESKTOP_ONLY_ROUTES, n) && a) return w.g(a),
        !1;
        var c = De.a.getUtmParams();

and

s = {
  isMobile: (i = function () {
    try {
      return !!window.navigator.appVersion.match(
        /(Mobile|Android|iPad|iPhone|iPod)/
      );
    } catch (e) {
      return !1;
    }
  }),
  isSupportedBrowser: function () {
    return (
      !i() &&
      (function () {
        try {
          return (
            a.b() &&
            o.a.canRecord() &&
            !!Object(r.a)("body")[0].requestFullscreen &&
            !!document.exitFullscreen &&
            !!window.URL &&
            !!window.AudioContext &&
            !!window.requestAnimationFrame &&
            !!window.cancelAnimationFrame &&
            !!window.MutationObserver &&
            !!window.Node &&
            !!new Audio().canPlayType("audio/mp3") &&
            !r.f.isUndefined(document.createElement("video").srcObject) &&
            !window.navigator.userAgent.match(
              /(Firefox\/48\.0|SE 2\.X MetaSr 1\.0)/
            ) &&
            !window.navigator.userAgent.match(/Firefox/)
          );
        } catch (e) {
          return !1;
        }
      })()
    );
  },
  getClientInfo: function () {
    return {
      extension_version: duo.extensionVersion,
      language: navigator.language,
      platform: navigator.platform,
      screen_height: screen.height,
      screen_width: screen.width,
      user_agent: navigator.userAgent,
      pixel_ratio: window.devicePixelRatio,
    };
  },
};

Well the last line of the tests… pretty much says everything:

            !window.navigator.userAgent.match(/Firefox/)

Everything else is true.

Let's move to needscontact.

[karlcow]

Maybe a sitepatch if we can doublecheck that this is working with a chrome UA.

[ksy36]

Apparently only Chrome and Opera are supported https://englishtest.duolingo.com/browsers.
I've tried spoofing as Chrome and after requesting permissions to use camera and microphone, I get this message:

[ksy36]

Looks like @duolingo is on github. Hi @aanavas and @hidekishima, we're wondering what could be a reason for not supporting Firefox here. Would you be able to pass this along to the relevant person or team?

[andrekhorie]

Hi all, thanks for reaching out! My name is André and I'm the engineering lead for the Duolingo English Test. I'll first give a bit of background on our product to explain the decision, and then talk briefly about what the issue was.

The Duolingo English Test is a high stakes language certification test widely used in use cases like university admissions. We have a mission of bringing an affordable test to test takers around the world -- for many of our competitors, the test taker has to pay USD 200-300 for the test alone (which is over one month of minimum wage in many countries), aside from airfare to travel to a test center, hotel, etc. As a result, many people in communities with very low income take our test.

As an online high stakes test, we need to certify that people are not cheating on the exam. One of the ways we do this is by recording the video and audio of the entire hour-long session, so that we can proctor the test with artificial intelligence and human proctoring.

Because we need to upload large video files for people who may not have broadband internet connection, we needed to be able to restrict the video file size. At the time of our decision to drop support for Firefox circa 2018, Firefox was generating overly large files. You'll have to forgive us for not remembering the exact context of the issue (it was quite a while ago, and there have been personnel changes since), but it may have been due to how Firefox was following user media constraints.

To note: We haven't revisited the 2018 decision, but our engineering team is working on things that will likely render this Github issue obsolete in coming months.

[ksy36]

Thanks for the detailed response @andrekhorie 👍