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I can't get javascript enabled using the normal process on Firefox 40.0.2. How can I do this?

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  • 53 have this problem
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  • Last reply by fdorow

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I loaded firefox 40.0.2 and I can't get Javascript enabled. I've gone into the java screen menu and javascript is enabled, but all of my applications that are running javascript doesn't see it as being enabled. Javascript is working on IE, but I'd prefer to continue using Firefox.

I loaded firefox 40.0.2 and I can't get Javascript enabled. I've gone into the java screen menu and javascript is enabled, but all of my applications that are running javascript doesn't see it as being enabled. Javascript is working on IE, but I'd prefer to continue using Firefox.

Chosen solution

You can check the network.protocol-handler.external.javascript pref on the about:config page to make sure that it is set to default (false).

You can use the search bar on the about:config page to filter for javascript. If other javascript prefs show user set (bold) then you can reset them as well.

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.

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Is it occured in your smart phone...????.

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No. It's on my desktop

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Javascript is enabled by default, and there is no GUI to disable it. What makes you believe it is disabled in the first place?

I've gone into the java screen menu

What is the 'java screen menu'? Note, Java is something completely different than Javascript. For more information - Google is your friend.

all of my applications that are running javascript

What applications?

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Thanks for the thoughts.

Attached is a screenshot of the error message I'm receiving when an application is trying to access javascript. This doesn't come up when running the application in IE.

Also, below are the instructions to enable javascript in Firefox if it isn't enabled (which be default it is enabled). On my system, it says it's enabled, but something is blocking my programs to be able to run it.


1) Open a new Firefox browser window or tab.
 2) Copy the following then paste it into the Firefox address bar: about:config
 3) Hit the Enter key.
 4) On the following page, click the button: "I'll be careful, I promise!"
 5) Find the javascript.enabled row under the Preference Name heading.
 6) Double-click anywhere within the javascript.enabled row to toggle the value from "False" to "True".
 7)  Finally, refresh your browser.
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Seçilmiş Həll

You can check the network.protocol-handler.external.javascript pref on the about:config page to make sure that it is set to default (false).

You can use the search bar on the about:config page to filter for javascript. If other javascript prefs show user set (bold) then you can reset them as well.

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.

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It was the network.protocol-handler.external.javascript pref that was set to True. I toggled it to set it to false, reloaded Firefox and things seem to work.

Thank you very much.

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You're welcome.

Do you have any idea how this pref got changed?

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I'm not sure how it might have gotten changed. The only appl that I've loaded since I re-imaged my laptop has been the Shrew soft VPN.