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Javascript settings in Firefox

Machine_Silver
Machine_Silver
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I am sure it is just my lack of knowledge, me doing something silly and/or missing the obvious, but I am a bit confused about Java and JavaScript.

Due to recent JavaScript exploits, I wanted to try run my browsers with it disabled. I realize that Java and JavaScript are two different things but firstly, I uninstalled Java via the control panel. After this the Java Plug-ins disappeared from Firefox. As I understand it, this now means my browsers will not run Java Applets.

So, then to JavaScripts. In Firefox, if I go to say www.vodafone.co.uk, the home page will not display correctly unless I tick the "Enable JavaScript" option.

My question is therefore, is the ability to run JavaScripts a built in feature of Firefox and totally unrelated to whether Java itself is installed on the PC? If this is so then also, how does this relate to Java versions, i.e. Java version 6 update 31, fixes the Flashback exploit but how does the JavaScript implementation in Firefox get updated or is this exploit only applicable to Java applets and not JavaScripts?

If someone could explain I would be most grateful.

Kind regards

I am sure it is just my lack of knowledge, me doing something silly and/or missing the obvious, but I am a bit confused about Java and JavaScript. Due to recent JavaScript exploits, I wanted to try run my browsers with it disabled. I realize that Java and JavaScript are two different things but firstly, I uninstalled Java via the control panel. After this the Java Plug-ins disappeared from Firefox. As I understand it, this now means my browsers will not run Java Applets. So, then to JavaScripts. In Firefox, if I go to say www.vodafone.co.uk, the home page will not display correctly unless I tick the "Enable JavaScript" option. My question is therefore, is the ability to run JavaScripts a built in feature of Firefox and totally unrelated to whether Java itself is installed on the PC? If this is so then also, how does this relate to Java versions, i.e. Java version 6 update 31, fixes the Flashback exploit but how does the JavaScript implementation in Firefox get updated or is this exploit only applicable to Java applets and not JavaScripts? If someone could explain I would be most grateful. Kind regards

由Machine_Silver于修改

所有回复 (2)

user66338
user66338
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Hello,

yes, Java and JavaScript settings and preferences for interactive web pages are two different things, really.

Java applets are small programs coded in the Java programming language, they're NOT part of Firefox and, if I recall correctly, Java applets *may* as well have access to your computer (you need to confirm it every time). JavaScript coded scripts run sandboxed, which means that they don't have access to anything outside the website. If they do, this is a security issue and should be fixed immediately.

To your questions:

Yes, JavaScript is unrelated to Java and JavaScript can run when no Java Runtime Environment is installed. JavaScript is part of Firefox. When Java gets updated, it fixes Java-related issues, like the exploit you mentioned above. JavaScript most likely doesn't have this exploit.

The JavaScript engine gets updated each time Firefox does. Thus, you should be running the latest version anyway.

Machine_Silver
Machine_Silver 提问者
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I appreciate you taking the time to post this clear and informative reply.

Thanks very much.

Kind regards