1345198 - "Select a Device" missing from Responsive Design Mode

Status: RESOLVED INVALID

(DevTools :: Responsive Design Mode, defect)

Description

[thumbsoup]

Attachment: Missing Select a Device in UI in Responsive Design Mode.png

User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Firefox/52.0
Build ID: 20170302120751

Steps to reproduce:

1. go to any website such as https://news.ycombinator.com/

2. In Firefox, go to Tools, then Web Developer, then select Responsive Design Mode

3. There is no "Select a Device" control shown. That whole bar which is supposed to appear above the viewport does not display for me.

4. I tried this again in Firefox Safe Mode, with add ons disabled, and it still occurs.


Actual results:

"Select a Device" feature does not display.  I just learned about this feature from the Firefox Developer Tools page for Responsive Design Mode:

https://developer.mozilla.org/en-US/docs/Tools/Responsive_Design_Mode



Expected results:

According to Firefox Developer tools documentation, I should have seen:

"Just above the viewport you'll see a label "no device selected": click this to see a list of device names. Select a device, and Responsive Design Mode will set the following properties to match the selected device..."

Comment 1

[Loic]

I tested FF52, it works for me, see my screenshot: http://i.imgur.com/pWPvAyt.jpg
But I see you have the old RDM layout, because you disabled e10s. Could you test with e10s enabled (about:config > browser.tabs.remote.autostart=true).

Comment 2

[thumbsoup]

Thanks for responding. I changed that configuration to True. Still get problem.  However, in my Config, there are 2 entries for that setting? I don't know if that matters.

browser.tabs.remote.autostart

and then another right below it, with the number 2 as a suffix at the end.  This is ALSO set to True.

browser.tabs.remote.autostart.2

Comment 3

[Loic]

What do you have for the line "multiprocess windows" in about:support?

By default, e10s is enabled in a fresh profile with browser.tabs.remote.autostart=false (e10s disabled by user) and browser.tabs.remote.autostart.2=true (e10s enabled by default).
If you force browser.tabs.remote.autostart=true, e10s will be set as enabled by the user.

Comment 4

[Loic]

In addition, could you add a screenshot of RDM with e10s enabled.

Comment 5

[J. Ryan Stinnett [:jryans] (Use needinfo, replies may be slow)]

Here's an additional support doc about multiprocess support:

https://support.mozilla.org/t5/Manage-preferences-and-add-ons/Enable-multiprocess-support/ta-p/1371917

Comment 6

[thumbsoup]

Attachment: about config Firefox 3-9-2017.png

Comment 7

[thumbsoup]

Attachment: Responsive Design Mode example Firefox 52 3-9-2017.png

Comment 8

[thumbsoup]

1. Multiprocess windows is Disabled by plugin in about:support

2. attached 2 screenshots.  My about:config, and then RDM example

3. I read doc on Multiprocess support (thanks).  The setting in about:config to Force it, I don't see in my about:config.  

I will try adding it manually, see what happens.

Comment 9

[thumbsoup]

Attachment: Responsive Design Mode after force multiprocess support Firefox 52 3-9-2017.png

Comment 10

[thumbsoup]

RDM seems to work for me, after Force multiprocess support by adding Preference to about:config, and setting boolean to True.

See screenshot.

Thanks very much for your help, guys.  

Maybe this stays fixed?

Comment 11

[J. Ryan Stinnett [:jryans] (Use needinfo, replies may be slow)]

Great, this sounds like it's working "as expected", but I am sorry it was so surprising / confusing!

We're working in bug 1345515 to make the situation more obvious for the future.