Enable JavaScript in browsers

All modern browsers come with support available for JavaScript. Often, you may need to manipulate to enable or disable this support. This chapter explains the procedure to enable and disable JavaScript support in your browser: Internet Explorer, Firefox, Chrome, and Opera .

JavaScript in Internet Explorer

Here are simple steps to enable or disable JavaScript in IE:

Select Tools -> Internet Options from the menu.

Select Security tab from that dialog box.

Click to select Custom Level .

Drag the mouse wheel until you see Scripting option .

Select Enable under Active scripting .

Finally click OK and exit.

To disable JavaScript support in your IE, you need to select the Disable button under Active scripting .

JavaScript in Firefox

Here are the steps to enable or disable JavaScript in Firefox:

Open a new tab, write about: config in the address bar.

You will then see a warning dialog. Choose I'll be careful, I promise!

You will then see a list of configure options in your browser.

In the search bar, write javascript.enabled .

Here, you will find the option to enable or disable JavaScript by right-clicking on the value of that option, selecting toggle .

If javascript.enabled is true, it changes to false with pressing toggle . If javascript is disabled, it activates when you click toggle.

JavaScript in Chrome

Here are the steps to enable or disable JavaScript in Chrome:

Click on the menu at the top right of the browser .

Select Settings .

Click on Show advanced settings at the bottom of the page.

Under the Privacy area, click the Content settings button.

In the "JavaScript" area, select "Do not allow any site to run JavaScript" or "Allow all sites to run JavaScript (recommended)".

JavaScript in Opera

Here are the steps to enable or disable JavaScript in Opera:

From the menu, select Tools -> Preferences .

Select the Advanced option from the dialog box.

Select Content from the listed items.

Select Enable JavaScript checkbox.

Finally click Ok and exit.

To disable JavaScript in Opera, you should not select Enable JavaScript checkbox .

Warning about Non-JavaScript browsers

If you have to do something important using JavaScript, then you can display a warning message to users by using tags

You can add a noscript block directly after the script block as follows:

     language = "javascript" type = "text/javascript" >        
 
Bây giờ, nếu trình duyệt của người dùng không hỗ trợ JavaScript hoặc JavaScript không được kích hoạt, thì thông báo từ sẽ được hiển thị trên màn hình.
 
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