Firefox is already running, but is not responding ???

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Joined: December 13th, 2007, 9:43 am

Post Posted June 11th, 2019, 8:40 pm

I recently upgraded to Release v67.0.1. Since doing so this problem has occurred.

Does anyone know what causes this message to appear?


This message appears in a pop-up window in Firefox when clicking on a URL outside Firefox (in email message for example).

Any explanation for why this is happening? Thx, Rob
Last edited by unbob on June 16th, 2019, 8:13 pm, edited 1 time in total.

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Joined: January 30th, 2019, 9:38 am

Post Posted June 12th, 2019, 5:16 am

The message occurs when Firefox is running, and when something (a user, or a program) is trying to open Firefox, and one of two cases are happening. Either Firefox is in the process of closing, or the way the user / program is opening Firefox makes Firefox think it needs to use a different profile, and the -no-remote flag or -P is not set properly so it cannot open a second profile.
Some tweaks were added to Firefox 67.0.2 to which was released, but I don't know if they would help.
There are other threads where Firefox did open the links, but in a second profile that nobody wanted. See here: viewtopic.php?f=38&t=3050560

I don't know a solution you will like. If you are willing to follow the rules, I would suggest you post a bug report to
What are you using as an email client? Thunderbird? If you switch to Seamonkey for email, it can act as a full browser and you can have it open its email links in itself. Or, if you set anything other than Firefox to be the default browser that may reduce some of the symptoms. You could add a -no-remote flag or a -P and the name of one or a second profile to the launch command for Firefox in your email client. If you do that, you may need to customize a second Firefox profile to be somewhat similar to how you like Firefox to operate. Again, this may not work.

I guess you are not using Firefox Portable, but if you are, try going to their support forum, they may be working on some of these issues.

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Post Posted June 12th, 2019, 6:47 am

it is only -no-remote - this message appears when firefox wont accept further commands. -p or profilemanager dont change a bit.

if he is aware of only ONE profile then i would say his profile is damaged somehow, see his user agent here, which ofc is not regular, i would say he had screwed it
Mozilla/5.0 (en-us;)


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Post Posted June 12th, 2019, 7:03 am

You might like to try re-setting your UA. (User Agent)
> ... in_default
Ancient Amateur Astronomer
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Post Posted June 12th, 2019, 11:09 am

LIMPET235 wrote:Rob,
You might like to try re-setting your UA. (User Agent)
> ... in_default
Mine were already set to 'default'.


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Post Posted June 13th, 2019, 10:42 am

It still shows a corrupted user agent: Mozilla/5.0 (en-us;)

You can start Firefox in Safe Mode to check if one of the extensions is causing this. ... x-problems

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