This wikiHow teaches you how to enable Java support in Firefox, either for a specific website or the entire browser. This article will also discuss how to enable JavaScript in the Firefox browser. You can enable Java and JavaScript on the desktop version of the Firefox browser.
Step
Method 1 of 3: Allowing Java Content on Websites
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Step 1. Open Firefox
The app icon looks like an orange fox surrounding a blue globe.
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Step 2. Visit a site that uses Java
If there is a specific site you want to access and use Java, go to that site.
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Step 3. Wait for the Java message or command to appear
You can see an "Activate Java" (or similar) link in the middle of the page (or around the Java content).
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Step 4. Click the "Activate Java" link
These links are above or around the Java content you want to load.
If you see a message that Java is unsupported ("unsupported"), disabled ("disabled"), not installed ("not installed"), or something like that, instead of the "Activate Java" link, you cannot run the site in Firefox
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Step 5. Click Allow Now when prompted
This button appears in the upper-left corner of the Firefox window. After that, the website will be reloaded and the Java content will be displayed.
You can also click the “ Allow and Remember ” to add the website to the " Allowed " list.
Method 2 of 3: Enabling All Java Content
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Step 1. Understand the limitations of this method
Due to security concerns, the current version of Firefox (and possibly future versions) does not support Java. To enable Java content, you need to install a 32-bit version of Firefox and add a Java plug-in manually. This process can be followed on a Windows computer, but on a Mac, Firefox will automatically install in the 64-bit version so you won't be able to install Java on Firefox for Mac.
- Firefox will update if you close and reopen it. Once updated, the installed Java is unusable.
- Using older versions of Firefox increases the risk of getting a virus or malware on your computer.
- You will not be able to update older versions of Firefox. If updated, Java support will be removed.
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Step 2. Open the Java website
Visit https://java.com/en/download/ in a browser. You will need to download and install Java before you can add it as an add-on to Firefox.
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Step 3. Download and install Java
To download it:
- Click " Free Java Download ”.
- Click " Agree and Start Free Download ”.
- Double-click the downloaded Java installation file.
- Click " Yes ' when prompted.
- Click the button " Install ” at the bottom of the Java window.
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Step 4. Go to the Firefox 51 download page
Visit https://ftp.mozilla.org/pub/firefox/releases/51.0b9/ in a browser. On this page, you can download the latest Firefox version that supports Java.
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Step 5. Click the 32 bit link
Click the link firefox-51.0b9.win32.sdk.zip ” at the bottom of the list of links on this page.
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Step 6. Open the downloaded ZIP folder
Double-click the ZIP folder to open it.
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Step 7. Extract the contents of the ZIP folder
To do so:
- Click the tab " Extract ” at the top of the window.
- Click " Extract all ” on the displayed toolbar.
- Click " Extract ” which is below the pop-up window.
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Step 8. Open the extracted folder
Double click the folder firefox-51.0b9.win32.sdk ” (not the ZIP folder) to open it.
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Step 9. Open firefox-sdk folder
This is the only folder shown in the window.
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Step 10. Open the bin folder
Double-click the folder to open it (shown at the top of the window).
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Step 11. Scroll down and double click the Firefox app icon
This icon is in the middle of the page. After that, the Firefox 51 application will be opened.
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Step 12. Disable automatic updates
Type about:config into Firefox's address bar and press Enter, then follow these steps:
-
Click the button I accept the risk!
' when prompted.
- Click the search bar at the top of the page.
- Type in app.update.auto
- Double click the option " app.update.auto ” to change the value from " true " to " false ".
- Make sure you click " not now " or " Ask later ” if prompted to update the program.
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Step 13. Click the button
It's in the upper-right corner of the window. After that, a new menu will be displayed.
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Step 14. Click Add-ons
The option with the jigsaw piece icon is in the menu. After that, the “Add-Ons” page will be displayed.
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Step 15. Click the Plugins tab
This tab is on the left side of the page.
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Step 16. Look for the option " Java(TM) Platform"
Usually this option is shown at the bottom of the page.
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Step 17. Click the “Ask to Activate” drop-down box
This box is next to the " Java(TM) Platform " heading. After that, a drop-down menu will be displayed.
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Step 18. Click Always Activate
This option is in the drop-down menu. After that, Java will be enabled for any website you visit via Firefox version 51. However, keep in mind that you shouldn't update your browser at all.
If you accidentally update your browser (or have a browser installed), you can reinstall Firefox 51 by deleting the “ firefox-51.0b9.win32.sdk (not the ZIP folder), opened the ZIP folder with the same name and re-extracted its contents, and reopened the Firefox 51 application from the “ son ”.
Method 3 of 3: Enabling JavaScript
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Step 1. Open Firefox
The app icon looks like an orange fox surrounding a blue globe.
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Step 2. Visit the configuration page
Type about:config and press Enter key to access the page.
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Step 3. Click I accept the risk! when requested
It's a blue button in the middle of the page.
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Step 4. Look for the “JavaScript” option
Click the search bar, then type javascript.enabled to search for suitable results.
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Step 5. Review the JavaScript values/settings
If you see the " true " option under the " value " heading on the right side of the page, JavaScript is enabled. This option is a default Firefox setting.
If you see a " false " option under the " value " heading, move on to the next step
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Step 6. Change the JavaScript value/option to " true " if necessary
Double click the option " javascript.enabled ” at the top of the page. You can see the status under the heading " value " changed to " true ".