The quick way to turn on JavaScript in Opera is to select Tools and then Quick Preferences from the Opera menu bar.
(click on the image for a larger version)
The more complicated route, and the route with many more options, is to select Tools » Preferences » Advanced. Once you get the Advanced tab, click on Content from the selections on the left.
Put a check in the "Enable JavaScript" checkbox.
Then, click on the JavaScript Options button to the right on the same line, and you’ll get another series of checkboxes to control whether Opera lets JavaScript do certain things or not. Notice that I have all of the boxes unchecked. This is my preferred, more secure setting.
(click on the image for a larger version)
(click on the image for a larger version)
Check or uncheck the boxes you want (I want them all unchecked) and then click the OK button. Then, click the OK button on the Peferences window.
Now, you should be all set, with JavaScript operational in Opera.
Please note that some other programs also may attempt to control whether JavaScript works or not. Sunbelt Personal Firewall, which I use, is an example of a firewall program that can allow or prevent JavaScript execution by the browser. However, I do not use its functions to prevent JavaScript or to block advertising.
Note that Java and JavaScript are not the same thing. Although they can both be used with web pages, their common feature is the four characters J a v a.
On a final note, JavaScript is a language. Each browser (IE, Firefox, Opera, etc.) has its own JavaScript interpreter that takes the JavaScript commands that are in a web page, and then executes them.
Just because one web browser does not handle a JavaScript function securely does not make JavaScript insecure — it is simply another example of a problem with an individual web browser.
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