How to Enable Java in Firefox

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Easily turn on Java in Firefox
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This wikiHow teaches you how to turn on Java support in Firefox, both on a per-website basis and across the entire browser, as well as how to enable JavaScript for your Firefox browser. You can enable both Java and JavaScript in the desktop version of Firefox.

Method 1
Method 1 of 3:

Allowing Java Content on a Website

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    Its app icon resembles an orange fox wrapped around a blue globe.
  2. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/4\/41\/Enable-Java-in-Firefox-Step-2-Version-5.jpg\/v4-460px-Enable-Java-in-Firefox-Step-2-Version-5.jpg","bigUrl":"\/images\/thumb\/4\/41\/Enable-Java-in-Firefox-Step-2-Version-5.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-2-Version-5.jpg","smallWidth":460,"smallHeight":348,"bigWidth":728,"bigHeight":551,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    If there's a particular site that you want to access using Java, go to that site.
    Advertisement
  3. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/d\/d7\/Enable-Java-in-Firefox-Step-3-Version-5.jpg\/v4-460px-Enable-Java-in-Firefox-Step-3-Version-5.jpg","bigUrl":"\/images\/thumb\/d\/d7\/Enable-Java-in-Firefox-Step-3-Version-5.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-3-Version-5.jpg","smallWidth":460,"smallHeight":344,"bigWidth":728,"bigHeight":545,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    You should see a link in the middle of the page (or the Java content area) that says "Activate Java" or something similar. [1]
  4. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/5\/55\/Enable-Java-in-Firefox-Step-4-Version-5.jpg\/v4-460px-Enable-Java-in-Firefox-Step-4-Version-5.jpg","bigUrl":"\/images\/thumb\/5\/55\/Enable-Java-in-Firefox-Step-4-Version-5.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-4-Version-5.jpg","smallWidth":460,"smallHeight":348,"bigWidth":728,"bigHeight":550,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    It should be on or near the Java content that you want to load.
    • If you see a message that says Java is "unsupported", "disabled", "not installed", or something similar instead of the "Activate Java" link, you cannot run the site in question on Firefox.
  5. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/f\/fe\/Enable-Java-in-Firefox-Step-5-Version-2.jpg\/v4-460px-Enable-Java-in-Firefox-Step-5-Version-2.jpg","bigUrl":"\/images\/thumb\/f\/fe\/Enable-Java-in-Firefox-Step-5-Version-2.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-5-Version-2.jpg","smallWidth":460,"smallHeight":347,"bigWidth":728,"bigHeight":549,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    It should appear in the upper-left side of the Firefox window. This will reload the website with the Java content enabled.
    • You can also click Allow and Remember to place the site on Firefox's "Allowed" list.
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Method 2
Method 2 of 3:

Enabling All Java Content

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  1. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/a\/af\/Enable-Java-in-Firefox-Step-6-Version-2.jpg\/v4-460px-Enable-Java-in-Firefox-Step-6-Version-2.jpg","bigUrl":"\/images\/thumb\/a\/af\/Enable-Java-in-Firefox-Step-6-Version-2.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-6-Version-2.jpg","smallWidth":460,"smallHeight":344,"bigWidth":728,"bigHeight":544,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    Due to security issues, current versions of Firefox do not support Java, nor will future versions. To enable Java content, you'll have to install an old, 32-bit version of Firefox and then manually add the Java plugin. This is possible on Windows computers, but Firefox for Mac defaults to 64-bit, making it impossible to install Java for Firefox on a Mac. [2]
    • Closing and re-opening Firefox may result in Firefox updating, which will render Java unusable.
    • Using an old version of Firefox increases the risk of contracting a computer virus or running into malware.
    • You can never update your old version of Firefox, as doing so will remove your Java support.
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    Go to https://www.java.com/en/download/ in a browser. You'll need to download and install Java before you can install it as a plugin in Firefox.
  3. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/b\/bf\/Enable-Java-in-Firefox-Step-8-Version-2.jpg\/v4-460px-Enable-Java-in-Firefox-Step-8-Version-2.jpg","bigUrl":"\/images\/thumb\/b\/bf\/Enable-Java-in-Firefox-Step-8-Version-2.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-8-Version-2.jpg","smallWidth":460,"smallHeight":346,"bigWidth":728,"bigHeight":547,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    To do so:
    • Click Free Java Download
    • Click Agree and Start Free Download
    • Double-click the downloaded Java setup file.
    • Click Yes when prompted.
    • Click Install at the bottom of the Java window.
  4. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/7\/71\/Enable-Java-in-Firefox-Step-9-Version-2.jpg\/v4-460px-Enable-Java-in-Firefox-Step-9-Version-2.jpg","bigUrl":"\/images\/thumb\/7\/71\/Enable-Java-in-Firefox-Step-9-Version-2.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-9-Version-2.jpg","smallWidth":460,"smallHeight":346,"bigWidth":728,"bigHeight":547,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    Go to https://ftp.mozilla.org/pub/firefox/releases/51.0b9/ in a browser. This is where you can download the last version of Firefox that supported Java.
  5. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/4\/47\/Enable-Java-in-Firefox-Step-10-Version-2.jpg\/v4-460px-Enable-Java-in-Firefox-Step-10-Version-2.jpg","bigUrl":"\/images\/thumb\/4\/47\/Enable-Java-in-Firefox-Step-10-Version-2.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-10-Version-2.jpg","smallWidth":460,"smallHeight":344,"bigWidth":728,"bigHeight":544,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    Click the firefox-51.0b9.win32.sdk.zip link near the bottom of the list of links on this page.
  6. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/8\/88\/Enable-Java-in-Firefox-Step-11-Version-2.jpg\/v4-460px-Enable-Java-in-Firefox-Step-11-Version-2.jpg","bigUrl":"\/images\/thumb\/8\/88\/Enable-Java-in-Firefox-Step-11-Version-2.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-11-Version-2.jpg","smallWidth":460,"smallHeight":348,"bigWidth":728,"bigHeight":551,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    Double-click the ZIP folder to do so.
  7. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/3\/3b\/Enable-Java-in-Firefox-Step-12-Version-2.jpg\/v4-460px-Enable-Java-in-Firefox-Step-12-Version-2.jpg","bigUrl":"\/images\/thumb\/3\/3b\/Enable-Java-in-Firefox-Step-12-Version-2.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-12-Version-2.jpg","smallWidth":460,"smallHeight":346,"bigWidth":728,"bigHeight":548,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    To do this:
    • Click the Extract tab at the top of the window.
    • Click Extract all in the resulting toolbar.
    • Click Extract at the bottom of the pop-up window.
  8. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/1\/16\/Enable-Java-in-Firefox-Step-13-Version-2.jpg\/v4-460px-Enable-Java-in-Firefox-Step-13-Version-2.jpg","bigUrl":"\/images\/thumb\/1\/16\/Enable-Java-in-Firefox-Step-13-Version-2.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-13-Version-2.jpg","smallWidth":460,"smallHeight":346,"bigWidth":728,"bigHeight":548,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    Double-click the firefox-51.0b9.win32.sdk folder (not the ZIP one) to open it.
  9. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/0\/00\/Enable-Java-in-Firefox-Step-14-Version-2.jpg\/v4-460px-Enable-Java-in-Firefox-Step-14-Version-2.jpg","bigUrl":"\/images\/thumb\/0\/00\/Enable-Java-in-Firefox-Step-14-Version-2.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-14-Version-2.jpg","smallWidth":460,"smallHeight":348,"bigWidth":728,"bigHeight":550,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    It's the only folder in the window.
  10. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/5\/5e\/Enable-Java-in-Firefox-Step-15-Version-2.jpg\/v4-460px-Enable-Java-in-Firefox-Step-15-Version-2.jpg","bigUrl":"\/images\/thumb\/5\/5e\/Enable-Java-in-Firefox-Step-15-Version-2.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-15-Version-2.jpg","smallWidth":460,"smallHeight":345,"bigWidth":728,"bigHeight":546,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    Double-click this folder, which is near the top of the window, to do so.
  11. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/d\/de\/Enable-Java-in-Firefox-Step-16.jpg\/v4-460px-Enable-Java-in-Firefox-Step-16.jpg","bigUrl":"\/images\/thumb\/d\/de\/Enable-Java-in-Firefox-Step-16.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-16.jpg","smallWidth":460,"smallHeight":346,"bigWidth":728,"bigHeight":548,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    It's near the middle of the page. This will prompt the Firefox 51 app to open.
  12. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/5\/54\/Enable-Java-in-Firefox-Step-17.jpg\/v4-460px-Enable-Java-in-Firefox-Step-17.jpg","bigUrl":"\/images\/thumb\/5\/54\/Enable-Java-in-Firefox-Step-17.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-17.jpg","smallWidth":460,"smallHeight":345,"bigWidth":728,"bigHeight":546,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    Type about:config into the Firefox address bar and press ↵ Enter , then do the following:
    • Click I accept the risk! when prompted.
    • Click the search bar at the top of the page.
    • Type in app.update.auto
    • Double-click the app.update.auto result to change its value from "true" to "false".
    • Be sure to click Not now or Ask later if ever prompted to update.
  13. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/a\/a6\/Enable-Java-in-Firefox-Step-18.jpg\/v4-460px-Enable-Java-in-Firefox-Step-18.jpg","bigUrl":"\/images\/thumb\/a\/a6\/Enable-Java-in-Firefox-Step-18.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-18.jpg","smallWidth":460,"smallHeight":346,"bigWidth":728,"bigHeight":547,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    It's in the upper-right side of the window. A menu will appear.
  14. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/0\/05\/Enable-Java-in-Firefox-Step-19.jpg\/v4-460px-Enable-Java-in-Firefox-Step-19.jpg","bigUrl":"\/images\/thumb\/0\/05\/Enable-Java-in-Firefox-Step-19.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-19.jpg","smallWidth":460,"smallHeight":346,"bigWidth":728,"bigHeight":547,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    This puzzle piece-shaped icon is in the menu. Doing so will open the Add-Ons page.
  15. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/f\/fa\/Enable-Java-in-Firefox-Step-20.jpg\/v4-460px-Enable-Java-in-Firefox-Step-20.jpg","bigUrl":"\/images\/thumb\/f\/fa\/Enable-Java-in-Firefox-Step-20.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-20.jpg","smallWidth":460,"smallHeight":344,"bigWidth":728,"bigHeight":545,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    It's on the left side of the page.
  16. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/7\/77\/Enable-Java-in-Firefox-Step-21.jpg\/v4-460px-Enable-Java-in-Firefox-Step-21.jpg","bigUrl":"\/images\/thumb\/7\/77\/Enable-Java-in-Firefox-Step-21.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-21.jpg","smallWidth":460,"smallHeight":345,"bigWidth":728,"bigHeight":546,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    You'll usually find this option near the bottom of the page.
  17. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/b\/b2\/Enable-Java-in-Firefox-Step-22.jpg\/v4-460px-Enable-Java-in-Firefox-Step-22.jpg","bigUrl":"\/images\/thumb\/b\/b2\/Enable-Java-in-Firefox-Step-22.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-22.jpg","smallWidth":460,"smallHeight":348,"bigWidth":728,"bigHeight":550,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    It's to the right of the "Java(TM) Platform" heading. A drop-down menu will appear.
  18. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/3\/35\/Enable-Java-in-Firefox-Step-23.jpg\/v4-460px-Enable-Java-in-Firefox-Step-23.jpg","bigUrl":"\/images\/thumb\/3\/35\/Enable-Java-in-Firefox-Step-23.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-23.jpg","smallWidth":460,"smallHeight":345,"bigWidth":728,"bigHeight":546,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    This option is in the drop-down menu. Doing so will activate Java for any website that you visit in this version of Firefox, though you must be careful not to update Firefox at all.
    • If you accidentally update Firefox or an update gets pushed through, you can reinstall Firefox 51 by deleting the firefox-51.0b9.win32.sdk folder (not the ZIP version), opening the ZIP folder of the same name and re-extracting it, and then re-opening the Firefox 51 app from within the bin folder.
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Method 3
Method 3 of 3:

Enabling JavaScript

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  1. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/d\/d5\/Enable-Java-in-Firefox-Step-24.jpg\/v4-460px-Enable-Java-in-Firefox-Step-24.jpg","bigUrl":"\/images\/thumb\/d\/d5\/Enable-Java-in-Firefox-Step-24.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-24.jpg","smallWidth":460,"smallHeight":344,"bigWidth":728,"bigHeight":545,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    Its app icon resembles an orange fox wrapped around a blue globe.
  2. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/0\/0b\/Enable-Java-in-Firefox-Step-25.jpg\/v4-460px-Enable-Java-in-Firefox-Step-25.jpg","bigUrl":"\/images\/thumb\/0\/0b\/Enable-Java-in-Firefox-Step-25.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-25.jpg","smallWidth":460,"smallHeight":344,"bigWidth":728,"bigHeight":545,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    Type in about:config and press ↵ Enter to do so.
  3. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/6\/6c\/Enable-Java-in-Firefox-Step-26.jpg\/v4-460px-Enable-Java-in-Firefox-Step-26.jpg","bigUrl":"\/images\/thumb\/6\/6c\/Enable-Java-in-Firefox-Step-26.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-26.jpg","smallWidth":460,"smallHeight":345,"bigWidth":728,"bigHeight":546,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    It's a blue button in the middle of the page.
  4. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/8\/8a\/Enable-Java-in-Firefox-Step-27.jpg\/v4-460px-Enable-Java-in-Firefox-Step-27.jpg","bigUrl":"\/images\/thumb\/8\/8a\/Enable-Java-in-Firefox-Step-27.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-27.jpg","smallWidth":460,"smallHeight":346,"bigWidth":728,"bigHeight":548,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    Click the search bar, then type in javascript.enabled to search for the matching result.
  5. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/1\/15\/Enable-Java-in-Firefox-Step-28.jpg\/v4-460px-Enable-Java-in-Firefox-Step-28.jpg","bigUrl":"\/images\/thumb\/1\/15\/Enable-Java-in-Firefox-Step-28.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-28.jpg","smallWidth":460,"smallHeight":348,"bigWidth":728,"bigHeight":550,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    If you see "true" below the "value" heading that's on the right side of the page, JavaScript is currently enabled; this is the default Firefox setting.
    • If you see "false" below the "value" heading, proceed.
  6. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/5\/58\/Enable-Java-in-Firefox-Step-29.jpg\/v4-460px-Enable-Java-in-Firefox-Step-29.jpg","bigUrl":"\/images\/thumb\/5\/58\/Enable-Java-in-Firefox-Step-29.jpg\/aid2908639-v4-728px-Enable-Java-in-Firefox-Step-29.jpg","smallWidth":460,"smallHeight":348,"bigWidth":728,"bigHeight":550,"licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a> (screenshot)<br>\n<\/p><\/div>"}
    Double-click javascript.enabled near the top of the page. You should see the status below the "value" heading change to "true".
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      References

      1. ↑ https://support.mozilla.org/en-US/kb/how-allow-java-trusted-sites
      2. ↑ https://support.mozilla.org/en-US/questions/932623

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