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CBSnews.com sends desktop version to Firefox OS smartphones, video won't work

Assigned to


Tech Evangelism
3 years ago
2 years ago


(Reporter: hallvors, Assigned: karlcow)


Firefox Tracking Flags

(Not tracked)


(Whiteboard: [mobile-compat-form] [country-us] [serversniff] [sitewait] [video], URL)



3 years ago
Site: http://www.cbsnews.com/video/watch/?id=7421030n
CBSnews.com sends desktop version to Firefox OS smartphones, video won't work

:: Steps To Reproduce

This site intends to send mobile phones a mobile version, but fails to detect Firefox OS smartphones as mobile. This means the content is larger than the screen and the video fails to play.

Browser detection happens at the backend. Here's some analysis of the HTTP traffic, note the missing redirect for Firefox OS compared to Firefox on Android and Safari on iPhone: Firefox Android and Safari on iPhone are redirected to http://www.cbsnews.com/48-hours, Firefox OS not redirected

Selected HTTP response headers (Firefox OS, Firefox on Android, Safari on iPhone):

Response for: 'Mozilla/5.0 (Mobile; rv:29.0) Gecko/29.0 Firefox/29.0'
Response Status: 200
content-length: 30074
content-type: text/html; charset=UTF-8

Response for: 'Mozilla/5.0 (Android; Mobile; rv:26.0) Gecko/26.0 Firefox/26.0'
Response Status: 302
content-length: 206
location: http://www.cbsnews.com/48-hours
content-type: text/html; charset=UTF-8

Response for: 'Mozilla/5.0 (iPhone; CPU iPhone OS 6_0 like Mac OS X) AppleWebKit/536.26 (KHTML, like Gecko) Version/6.0 Mobile/10A5376e Safari/8536.25'
Response Status: 302
content-length: 206
location: http://www.cbsnews.com/48-hours
content-type: text/html; charset=UTF-8

:: Expected Result

Mobile content

:: Actual Result

Desktop site

:: Additional Information

Software Version: 2.0
Reporter's User Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:32.0) Gecko/20100101 Firefox/32.0


3 years ago
Ever confirmed: true
Whiteboard: [mobile-compat-form] → [mobile-compat-form] [country-us] [serversniff] [contactready] [video]

Comment 1

3 years ago
This is related to the same site and video bug 841005
See Also: → bug 841005

Comment 2

3 years ago
When entering http://cbsnews.com/ 

Receive the desktop version
* Firefox OS

Receive the mobile version
* Chrome

Note that it sends a cookie for specifying the version you are on. It means that for example for testing on Firefox Desktop faking UA. You need to make sure to flush the cookies in between each tests.

The cookie is:


It also becomes part of the homepage
    var _utag_obj={"isEnabled":true,"deviceType":"mobile","isDev":"0","pageType":"front_door","siteHier":["frontdoor"],"siteSection":"frontdoor","siteType":"responsive web","topicId":["1ba86ba8-758d-11e2-9d12-0018fe8a00b0"],"topicName":["frontdoor"],"bkSiteId":3330,"limit":4,"siteName":"cbsnews","tealium":{"profile":"cbsnewssite","env":"prod"}};    

When faking Chrome Mobile UA using Gecko rendering engine, we receive a working Web site. (Videos to be tested)

Comment 3

3 years ago
Hallvord, I can't start the video when faking Chrome UA. When clicking it disappears and leaves a blank space.
Flags: needinfo?(hsteen)

Comment 4

3 years ago
There's some version-number sensitive browser detection involved here. So, for example:

User-Agent: Mozilla/5.0 (Mobile; rv:28.0) Gecko/28.0 Firefox/28.0 - mobile
User-Agent: Mozilla/5.0 (Mobile; rv:29.0) Gecko/29.0 Firefox/29.0 - desktop
User-Agent: Mozilla/5.0 (Mobile; rv:30.0) Gecko/30.0 Firefox/20.0 - mobile

This makes testing harder :-/
Flags: needinfo?(hsteen)

Comment 5

3 years ago
Karl: what I see (when I've finally managed to set the User-Agent on the Flame to one with a version number CBS thinks is mobile & cleared enough cookies) is that the ad plays, but the video not. Sounds like the familiar issue with not being able to play two videos in a web page. See bug 1029552 - presumably fixed but I don't think the fix is in the build this phone is running just yet..
Depends on: 1029552
Flags: needinfo?(kdubost)

Comment 6

3 years ago
Hallvord, good find about the version number but it's even a bit worse.

First of all the minimal UA string to trigger fly_device=mobile is:

'User-Agent:Mozilla/5.0 Mobile Gecko/28 Firefox/28.0'

If you change one thing of this it will go back to desktop.
Now for the fun…

'User-Agent:Mozilla/5.0 Mobile Gecko/28 Firefox/16.0' → mobile
'User-Agent:Mozilla/5.0 Mobile Gecko/28 Firefox/17.0' → desktop
'User-Agent:Mozilla/5.0 Mobile Gecko/28 Firefox/18.0' → desktop
'User-Agent:Mozilla/5.0 Mobile Gecko/28 Firefox/26.0' → mobile
'User-Agent:Mozilla/5.0 Mobile Gecko/28 Firefox/27.0' → desktop
'User-Agent:Mozilla/5.0 Mobile Gecko/28 Firefox/28.0' → mobile
'User-Agent:Mozilla/5.0 Mobile Gecko/28 Firefox/29.0' → desktop
'User-Agent:Mozilla/5.0 Mobile Gecko/28 Firefox/30.0' → mobile
'User-Agent:Mozilla/5.0 Mobile Gecko/28 Firefox/31.0' → desktop
'User-Agent:Mozilla/5.0 Mobile Gecko/28 Firefox/32.0' → mobile
'User-Agent:Mozilla/5.0 Mobile Gecko/28 Firefox/33.0' → desktop
'User-Agent:Mozilla/5.0 Mobile Gecko/28 Firefox/34.0' → mobile
'User-Agent:Mozilla/5.0 Mobile Gecko/28 Firefox/35.0' → desktop
'User-Agent:Mozilla/5.0 Mobile Gecko/28 Firefox/36.0' → desktop
'User-Agent:Mozilla/5.0 Mobile Gecko/28 Firefox/37.0' → desktop
'User-Agent:Mozilla/5.0 Mobile Gecko/28 Firefox/38.0' → desktop
'User-Agent:Mozilla/5.0 Mobile Gecko/28 Firefox/39.0' → desktop
and so on …

Here the black magick:

* The number after Gecko is not significant, BUT must be here.
* The number ".0" after Firefox is not significant, BUT must be here.
* The number after Firefox must be an even number for triggering mobile, an odd number for triggering desktop.
* The number after Firefox must be > 17 to get a mobile version.
* The number after Firefox must be < 35 to get a mobile version.

Flags: needinfo?(kdubost)

Comment 7

3 years ago
Clay Webster has quit CBS Interactive.
Trying to contact Blaise Tarr.
Assignee: nobody → kdubost
Whiteboard: [mobile-compat-form] [country-us] [serversniff] [contactready] [video] → [mobile-compat-form] [country-us] [serversniff] [sitewait] [video]

Comment 8

2 years ago
Sent a reminder to Blaise Tarr today.
We still have the same issue. 

Firefox OS is receiving the desktop version.
Firefox Android is receiving the mobile version.


2 years ago
Priority: -- → P5
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