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JavaScript executed through address bar is not working in Firefox 7, 8. For example, the code below works in Chrome, when I paste it into the address bar and press Enter:

javascript:alert("hello world!");

In the latest Firefox, it's not working. Why? How can I make it work?

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migrated from Nov 14 '11 at 21:27

This question came from our site for professional and enthusiast programmers.

What is your practical application of that feature? – Šime Vidas Nov 14 '11 at 14:56
You can find answer here. – Rizwan Nov 14 '11 at 14:56
i cant find any solution from your url – Vishnu Dina Nov 14 '11 at 14:58
i just need to run javascript through adress bar – Vishnu Dina Nov 14 '11 at 14:59
From that URL: "Starting in Firefox 6 javascript in the url-bar runs with a null security principal for security reasons. This means it's almost disabled. You need a bookmarklet or an add-on for a workaround." – Quentin Nov 14 '11 at 15:00

It's a security issue. Other browsers will follow this restriction...

Use firebug instead ;)

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If you want to execute javascript from url, then you have to use like this:

let's say, you have site: then in post.php, insert:

if (!empty($_GET['action']) && $_GET['action'] == myfunction ){
echo '<script>alert("Hi User");</script>';

after that, when you enter:

then the script will be shown.

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