1677058 - Firefox 83 on Windows 10 in SSB-mode reports as Firefox Android (KitKat)

Status: RESOLVED WONTFIX

(Firefox :: General, defect)

Description

[github]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:83.0) Gecko/20100101 Firefox/83.0

Steps to reproduce:

I'm using Firefox 83.0b10 on Intel Windows 10, 64-bit, with a 4k screen, with windows mostly maximised

1. Enable SSB (about:config, browser.ssb.enabled => true)

2. Open any website; for this test I'm using
   https://www.whatismybrowser.com/detect/what-is-my-user-agent

3. Note the user-agent reported; mine reports:
   Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:83.0) Gecko/20100101 Firefox/83.0

4. Click the ... menu on the address bar, click "Use This Site in App Mode"

5. In the new SSB-mode version of the page, note the user-agent; mine reports:
   Mozilla/5.0 (Android 4.4; Mobile; rv:83.0) Gecko/83.0 Firefox/83.0

If you do this on sites like Outlook.com/owa, you get forced into the mobile version of the Outlook page even on a massive screen

Actual results:

The non-SSB user-agent and the SSB user-agent are different, with the SSB user-agent being a mobile one (which gives a terrible experience on a large screen)

Expected results:

The SSB user-agent is the normal desktop one (or at least configurable)

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

Bugbug thinks this bug should belong to this component, but please revert this change in case of error.

Comment 2

[Petruta Horea [:phorea], Desktop QA]

Switching to General component, this is where most of the ssb bugs belong.

Comment 3

[Arun Das]

I can't reproduce this using Firefox 83.0. I get the same "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:83.0) Gecko/20100101 Firefox/83.0" in SSB window too. ¯_(ツ)_/¯

Comment 4

[Dave Townsend [:mossop]]

Closing per bug 1682593.