896266 - Cannot Run Firefox Nightly and Firefox at Same Time

Status: RESOLVED INVALID

(Firefox :: Untriaged, defect)

Description

[breck7]

Attachment: Screen Shot 2013-07-21 at 9.14.08 AM.png

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_7_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/30.0.1571.0 Safari/537.36

Steps to reproduce:

Installed Firefox Nightly. Had Firefox open.

Opened Nightly.


Actual results:

 Got this message:

"Close Firefox"

"A copy of Firefox is already open. Only one copy of Firefox can be open at a time."


Expected results:

Nightly opens fine alongside Firefox.

I think it would be neat to be able to have them open side by side. That way you could easily compare differences between the two. I bet it would be very useful for development.

Comment 1

[breck7]

Just another data point: Chrome Canary seems to work fine alongside Chrome.

Comment 2

[Tiziana Sellitto [:tiziana]]

Thanks for reporting this!
You can have two Firefox instances opened if you use different profiles. Try creating a new profile 
https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles

Comment 3

[Tiziana Sellitto [:tiziana]]

I'll close this one. Please reopens if you have problems trying with the suggestions of comment 2.

Comment 4

[Patrick Dark]

(In reply to breck7 from comment #0)
> "A copy of Firefox is already open. Only one copy of Firefox can be open at
> a time."

I got this error too. Apparently it happens when firefox.exe is running and you try to click "Finish" in the Nightly installer with the "Launch Nightly now" checkbox checked. It can be unclear why this is happening if (A) you don't know that Nightly considers itself to be the same program as Firefox, which doesn't allow multiple instances to run by default, or (B) firefox.exe is still running in the background despite no Firefox windows being open. (Presumably, such situations occur due to program misbehavior.)

(In reply to Tiziana Sellitto [:tiziana] from comment #2)
> Thanks for reporting this!
> You can have two Firefox instances opened if you use different profiles. Try
> creating a new profile 
> https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-
> firefox-profiles

This article is not directly helpful. Apparently, in order to run Firefox and Nightly side-by-side, one must edit the Windows shortcut to execute with the badly-named "-no-remote" flag in addition to creating multiple profiles.

In other words, "C:\Program Files (x86)\Nightly\firefox.exe" -p "Test Profile" is not sufficient. It must be ""C:\Program Files (x86)\Nightly\firefox.exe" -p "Test Profile" -no-remote". This flag isn't described in that article. (I did use the article's feedback mechanism to recommend it be updated to mention this flag.)

The stupid thing is that running Nightly as a separate program instance is not the default behavior like it is for, say, Opera Next. Instead, if Firefox is running and you click the Nightly icon, you get a new Firefox window. Conversely, if Nightly is running and you click the Firefox icon, you get a new Nightly window. Unless you set these flags manually, of course. That's very unintuitive behavior.

Comment 5

[Tiziana Sellitto [:tiziana]]

Sorry I didn't notice the article doesn't mention "no-remote"

Comment 6

[Jens]

Had the same problem. For all fellow googlers, here's who to run Nightly alongside the "normal", stable Firefox: http://superuser.com/questions/679797/how-to-run-firefox-nightly-alongside-firefox-at-the-same-time