Open Source JavaScript Browser Extensions and Plugins
Sort By:
JavaScript Browser Extensions and Plugins
View 202 business solutionsBrowse free open source JavaScript Browser Extensions and Plugins and projects below. Use the toggles on the left to filter open source JavaScript Browser Extensions and Plugins by OS, license, language, programming language, and project status.
-
MongoDB Atlas runs apps anywhereMongoDB Atlas gives you the freedom to build and run modern applications anywhere—across AWS, Azure, and Google Cloud. With global availability in over 115 regions, Atlas lets you deploy close to your users, meet compliance needs, and scale with confidence across any geography.
-
Enterprise-grade ITSM, for every businessFreshservice is an intuitive, AI-powered platform that helps IT, operations, and business teams deliver exceptional service without the usual complexity. Automate repetitive tasks, resolve issues faster, and provide seamless support across the organization. From managing incidents and assets to driving smarter decisions, Freshservice makes it easy to stay efficient and scale with confidence.
-
1
SweetAlert2
Beautiful, responsive, highly customizable popup boxes
SweetAlert2 offers a beautiful, responsive, highly customizable and accessible alternative to JavaScript’s popup boxes. It’s got zero dependencies, is compatible with most modern browsers, and offers a wealth of customization options. Your popup boxes can look exactly how you want them with various options for additional content, custom positioning, animation, background, and so much more! SweetAlert2 also supports various input types and offers a range of different themes. Visit their official website, https://sweetalert2.github.io/ to see all these custom features in action! -
2
Don't waste your time with compliance. Universal Bypass circumvents annoying link shorteners. Universal Bypass bypasses templates that are used on thousands of domains and it would be impossible for me to keep a complete list of domains that are bypassed. You would have to get a new Universal Bypass version and accept its new permissions for each new bypass. Custom Bypasses would be pretty pointless if you could only create them for sites that are already bypassed. Also known in the options as "Give and take the destinations of unbypassable shorteners.", this feature exists to bypass a respectable amount of link shorteners using CAPTCHAs and other forms of backend validation to make sure you've actually waited before you can proceed to the target link, to share this target with other Universal Bypass users, who come across the same link in the future, so they can proceed to the target immediately.
-
3
Buster
Captcha solver extension for humans
Save time by asking Buster to solve captchas for you. Buster is a Firefox extension which helps you to solve difficult captchas by completing reCAPTCHA audio challenges using speech recognition. Challenges are solved by clicking on the extension button at the bottom of the reCAPTCHA widget. It is not guaranteed that challenges are always solved, the limitations of the technology need to be considered. The continued development of Buster is made possible thanks to the support of awesome backers. If you'd like to join them, please consider contributing with Patreon, PayPal or Bitcoin. The success rate of the extension can be improved by simulating user interactions with the help of a client app. Follow the instructions from the extension's options to download and install the client app on Windows, Linux and macOS, or get the app from this repository. -
4
Stylus for Chrome
Stylus - Userstyles Manager
Stylus is a fork of Stylish for Chrome, also compatible with Firefox as a WebExtension. "Stylus" is a fork of the popular Stylish extension which can be used to restyle the web. Not "ish", but "us", as in "us" the actual users. Stylus is a fork of Stylish that is based on the source code of version 1.5.2, which was the most up-to-date version before the original developer stopped working on the project. The objective in creating Stylus was to remove any and all analytics, and return to a more user-friendly UI. We recognize that the ability to transfer your database from Stylish is important, so this is the one and only feature we've implemented from the new version. Two different optional code validators with user-configurable rules: CSSLint and Stylelint. Both validators use Web Worker API to run in a separate background thread inside the editor tab without blocking your interaction with the code. -
$300 in Free Credit Towards Top Cloud ServicesStart your project in minutes. After credits run out, 20+ products include free monthly usage. Only pay when you're ready to scale.
-
5
Adguard Browser Extension
AdGuard browser extension
AdGuard is a fast and lightweight ad-blocking browser extension that effectively blocks all types of ads and trackers. AdGuard is a fast and lightweight ad blocking browser extension that effectively blocks all types of ads and trackers on all web pages. We focus on advanced privacy protection features to not just block known trackers, but prevent web sites from building your shadow profile. Unlike its standalone counterparts (AG for Windows, Mac), the browser extension is completely free and open source. You can learn more about the difference here. AdGuard does not collect any information about you, and does not participate in any acceptable ads program. The only source of income we have is selling premium versions of our software, and we intend to keep it that way. AdGuard for Windows is not just another ad blocker, it is a multipurpose tool that combines all necessary features for the best web experience. It blocks ads and dangerous websites, speeds up page loading, etc. -
6
DuckDuckGo Browser Extensions
DuckDuckGo Privacy Essentials browser extension for Firefox, Chrome
Privacy, simplified. One super-charged app, multiple types of privacy protection. The DuckDuckGo app provides the most comprehensive online privacy protection with the push of a button. With one download, you get a new everyday browser that offers seamless protection while you search and browse, and even access to tracking protection for emails you receive. Protecting your privacy online is like protecting your home. Locking the front door won’t stop the most determined folks from getting inside, especially if you’ve left the back door and windows unlocked and an extra key under the doormat. That’s why we offer multiple types of privacy protection, most of which aren’t offered in most popular browsers by default. DuckDuckGo Private Search comes built-in, so you can easily search the web without being tracked. Automatically stop most hidden trackers (3rd-party scripts) from loading, which prevents companies from collecting and using (e.g. sale, ads, etc.). -
7
Translate Web Pages
Translate your page in real time using Google or Yandex
Translate your page in real time using Google or Yandex. It is not necessary to open new tabs. Now works with the NoScript Extension. Your current page is translated without having to open new tabs. It is possible to change the translation language. You can select to automatically translate. To change the translation engine just touch the Google Translate icon. To translate any website it is necessary to access and modify the text of the web pages. And the extension can only do that, with that permission. The pages are translated using the Google or Yandex translation engine (you choose). We do not collect any information. However, to translate, the contents of the web pages will be sent to Google or Yandex servers. You can also install via crx file, download the file using a download manager/or firefox. Activate developer mode and drag the file into the chromium extension manager. It doesn't work on Chrome/Edge. -
8
jQuery Validation Plugin
jQuery Validation Plugin library sources
The jQuery Validation Plugin provides drop-in validation for your existing forms, while making all kinds of customizations to fit your application really easy. This jQuery plugin makes simple clientside form validation easy, whilst still offering plenty of customization options. It makes a good choice if you’re building something new from scratch, but also when you’re trying to integrate something into an existing application with lots of existing markup. The plugin comes bundled with a useful set of validation methods, including URL and email validation, while providing an API to write your own methods. All bundled methods come with default error messages in english and translations into 37 other languages. The plugin was initially written and maintained by Jörn Zaefferer, a member of the jQuery team, lead developer on the jQuery UI team and maintainer of QUnit. It was started back in the early days of jQuery in 2006, and updated and improved since then. -
9
Automa
A chrome extension for automating your browser by connecting blocks
Automa is a browser extension for browser automation. From auto-fill forms, doing a repetitive task, taking a screenshot, to scraping data of the website, it's up to you what you want to do with this extension. Automa has provided various kinds of blocks that will help you do automation, and all you need to do is connect them. Want your workflow to run every day or every time you visit a specific website? You can set the workflow trigger on the trigger block. Try a workflow from the marketplace. There're dozens of workflows been shared by Automa users which you can add and customize. Auto-fill forms, do a repetitive task, take a screenshot, or scrape website data, the choice is yours. You can even schedule when the automation will execute! Browse the Automa marketplace where you can share and download workflows with others. -
Gemini 3 and 200+ AI Models on One PlatformBuild generative AI apps with Vertex AI. Switch between models without switching platforms.
-
10
Bitwarden Browser Extension
The Bitwarden browser extension vault
Bitwarden Browser Extension lets you integrate Bitwarden directly into your browser of choice. Bitwarden is an open source password management solution that stores all your sensitive information securely in an encrypted vault. With this extension, you will be able to easily and conveniently access Bitwarden through your browser. Bitwarden Browser Extension is written using the Web Extension API and Angular, and supports a variety of browsers. These include Chrome, Firefox, Opera, Edge, Safari and many other popularly used browsers. -
11
Ghostery
Ghostery Browser Extension for Firefox, Chrome, Opera and Edge
Ghostery helps you browse smarter by giving you control over ads and tracking technologies to speed up page loads, eliminate clutter, and protect your data. This is the unified code repository for the Ghostery browser extensions in Chrome, Firefox, Opera and Edge. Browse the web safer, faster & with less annoying ads. Equipped with award-winning AI anti-tracking technology to browse the websafe and quickly. Ghostery helps you stay informed about what companies are tracking you by listing the trackers on each website you visit. Granular control within the detailed view allows you to block and unblock specific trackers. With one click, always allow or forbid Ghostery to block trackers and protect your personal data on a specific site. Smart-Browsing automatically optimizes page performance as your browse. -
12
chromium-web-store
Allows adding extensions from chrome web store on ungoogled-chromium
Allows adding extensions from chrome web store on ungoogled-chromium. Also adds semi-automatic extension updating. This extension brings the following functionality to ungoogled-chromium (and other forks that lack web store support). Allows installing extensions directly from chrome web store. Automatically checks for updates to your installed extensions and displays them on the badge. Pin the Chromium Web Store badge in your browser's toolbar. (Badges are hidden by default). The badge will show a red number indicating available updates. Click on the badge, then click the name of any extension to install the latest version. This method will work for non-webstore extensions as well if they support it, including chromium web store itself. (See the section below if you are an extension developer and don't have your extension listed in the chrome web store.) -
13
Progressive Web Apps for Firefox
A tool to install, manage and use Progressive Web Apps (PWAs)
A tool to install, manage and use Progressive Web Apps (PWAs) in Mozilla Firefox. Progressive Web Apps (PWAs) are web apps that use web APIs and features along with a progressive enhancement strategy to bring a native app-like user experience to cross-platform web applications. Although Firefox supports many of Progressive Web App APIs, it does not support functionality to install them as a standalone system app with an app-like experience. This project creates a custom-modified Firefox runtime to allow websites to be installed as standalone apps and provides a console tool and browser extension to install, manage and use them. Command-line tool to install, manage and run Progressive Web Apps in Firefox. Extension to set up native programs, and install, manage and run PWAs and their profiles directly from the main Firefox browser. Isolated Firefox installation and profile(s) that stores the PWAs. -
14
user.js
Firefox privacy, security and anti-tracking: a comprehensive user.js
A user.js is a configuration file that can control Firefox settings - for a more technical breakdown and explanation, you can read more in the wiki. The arkenfox user.js is a template that aims to provide as much privacy and enhanced security as possible and to reduce tracking and fingerprinting as much as possible - while minimizing any loss of functionality and breakage (but it will happen). Everyone, experts included, should at least read the wiki, as it contains important information regarding a few user.js settings. Note that we do not recommend connecting over Tor on Firefox. Use the Tor Browser if your threat model calls for it, or for accessing hidden services. Also be aware that the arkenfox user.js is made specifically for desktop Firefox. Using it as-is in other Gecko-based browsers can be counterproductive, especially in the Tor Browser. -
15
SingleFile
Web Extension for saving a copy of complete web page in a single file
Web Extension for Firefox/Chrome/MS Edge and CLI tool to save a faithful copy of an entire web page in a single HTML file. SingleFile is a Web Extension (and a CLI tool) compatible with Chrome, Firefox (Desktop and Mobile), Microsoft Edge, Vivaldi, Brave, Waterfox, Yandex Browser, and Opera. It helps you to save a complete web page into a single HTML file. Wait until the page is fully loaded. Click on the SingleFile button in the extension toolbar to save the page. You can click again on the button to cancel the action when processing a page. Open the context menu by right-clicking the SingleFile button in the extension toolbar or on the webpage. It allows you to save the current tab, the selected content, the selected frame. With auto-save active, pages are automatically saved every time after being loaded (or before being unloaded if not). Right-click on the SingleFile button and select "Manage extension" (Firefox) / "Options" (Chrome) to open the options page. -
16
Web Archives
Browser extension for viewing archived and cached versions of websites
Browser extension for viewing archived and cached versions of web pages, available for Chrome, Edge and Safari. Web Archives is a browser extension that enables you to find archived and cached versions of web pages, and comes with support for more than 10 search engines. Searches can be initiated from the context menu and the browser toolbar. A diverse set of archive and cache sources are supported, which can be toggled and reordered from the extension's options. Visit the wiki for the full list of supported search engines. You may choose to allow the extension to run on every website, or grant access to the current website before a search. When you grant access only to the current website, access must also be granted to each search engine in order to view search results. A handful of search modes are offered that serve different use cases. The search mode can be set independently for the context menu and the browser toolbar from the extension's options. -
17
uBlock
uBlock: a fast, lightweight, and lean blocker for Chrome, Firefox
uBlock: a fast, lightweight, and lean blocker for Chrome, Firefox, and Safari. Available on the Chrome Web Store or for manual installation. Available to install from the homepage. Available for install from the homepage or from the App Store. Available on the Firefox Add-ons site, or for manual installation. Opera shares Chrome's underlying engine, so you can install uBlock simply by grabbing the latest release for Chrome.To benefit from uBlock's higher efficiency, it's advised that you don't use other blockers at the same time (such as AdBlock or Adblock Plus). uBlock will do as well or better than most popular ad blockers. It's important to note that blocking ads is not theft. Don't fall for this creepy idea. The ultimate logical consequence of blocking = theft is the criminalisation of the inalienable right to privacy. -
18
Search by Image
Browser extension for reverse image search, available for Chrome
Search by Image is a powerful browser extension for Safari that makes effortless reverse image searches possible, and comes with support for more than 30 search engines, such as Google, Bing, Yandex, Baidu and TinEye. Search by Image is an open source project made possible thanks to a community of awesome supporters. By purchasing the extension on the Mac App Store, you help support the continued development of the extension. The extension helps journalists and researchers verify the authenticity of images, and assists in the identification of false information on social media. Search by Image is also popular among photographers, helping artists explore how their work is shared on the web, while shoppers find it valuable for discovering similar products at discounted prices. The extension enables you to search for images from the context menu and the browser toolbar with the help of a diverse set of reverse image search engines, which can be toggled and reordered from th -
19
StackEdit
In-browser Markdown editor
Unrivalled writing experience. StackEdit’s Markdown syntax highlighting is unique. The refined text formatting of the editor helps you visualize the final rendering of your files. StackEdit provides very handy formatting buttons and shortcuts, thanks to PageDown, the WYSIWYG-style Markdown editor used by Stack Overflow. Whether you write, you review, you comment… StackEdit's layout provides you with the flexibility you need, without sacrifice. StackEdit’s Scroll Sync feature accurately binds the scrollbars of the editor panel and the preview panel to ensure that you always keep an eye on the output while writing. StackEdit can sync your files with Google Drive, Dropbox and GitHub. It can also publish them as blog posts to Blogger, WordPress and Zendesk. You can choose whether to upload in Markdown format, HTML, or to format the output using the Handlebars template engine. -
20
CanvasBlocker
A Firefox extension to protect from being fingerprinted
This add-on allows users to prevent websites from using some Javascript APIs to fingerprint them. Users can choose to block the APIs entirely on some or all websites (which may break some websites) or just block or fake its fingerprinting-friendly readout API. Canvas Blocker's default setting, and my favorite! All websites not on the white list or black list can use the protected APIs. But values obtained by the APIs are altered so that consistent fingerprinting is not possible. If a website is not listed on the white list or black list, the user will be asked if the website should be allowed to use the protected APIs each time they are called. Block the protected APIs only for websites on the black list. Ignore all lists and allow the protected APIs on all websites. -
21
Replace Google CDN
A Chrome plugin: Replace Google CDN with domestic
For well-known reasons, just substituting a domain name can continue to use the front-end public library provided by Google. Likewise, referencing these resources via the scripttag will instantly speed up your website access! Many websites, especially foreign websites, use Google's CDN in order to speed up the website. But in China, due to some reasons, the world's fastest CDN has become the world's slowest. So, I wrote this plugin/extension to replace Google's CDN with a domestic one. This plugin/extension can replace the cdn resources with domestic ones. -
22
Autoprefixer
Parse CSS and add vendor prefixes to CSS rules by Can I Use
PostCSS plugin to parse CSS and add vendor prefixes to CSS rules using values from Can I Use. It is recommended by Google and used in Twitter and Alibaba. Write your CSS rules without vendor prefixes (in fact, forget about them entirely). Autoprefixer will use the data based on current browser popularity and property support to apply prefixes for you. You can try the interactive demo of Autoprefixer. Autoprefixer uses Browserslist, so you can specify the browsers you want to target in your project with queries. It can help you get prefixes for: animations, transition, transform, grid, flex, flexbox and others. You can configure which browsers to generate prefixes for in the distribution. The IE grid layout polyfill is enabled, which is not by default in autoprefixer. Autoprefixer can be used to translate modern CSS Grid syntax into IE 10 and IE 11 syntax, but this polyfill will not work in 100% of cases. This is why it is disabled by default. -
23
bootstrap-datepicker
A datepicker for twitter bootstrap
Bootstrap-datepicker provides a flexible datepicker widget in the Bootstrap style. Versions are incremented according to semver. As with bootstrap’s own plugins, datepicker provides a data-api that can be used to instantiate datepickers without the need for custom javascript. You can disable datepicker’s data-api in the same way as you would disable other bootstrap plugins. Most options can be provided via data-attributes. An option can be converted to a data-attribute by taking its name, replacing each uppercase letter with its lowercase equivalent preceded by a dash, and prepending “data-date-” to the result. Methods are called on a datepicker by calling the datepicker function with a string first argument, followed by any arguments the method takes. -
24
Multi-Account Containers
Keep parts of your online life separated into color-coded tabs
Firefox Multi-Account Containers lets you keep parts of your online life separated into color-coded tabs. Cookies are separated by container, allowing you to use the web with multiple accounts and integrate Mozilla VPN for an extra layer of privacy. Under the hood, it separates website storage into tab-specific Containers. Cookies downloaded by one Container are not available to other Containers. You can even integrate individual Containers with Mozilla VPN to protect your browsing and location. With the Firefox Multi-Account Containers extension, you can sign in to two different accounts on the same site (for example, you could sign in to work email and home email in two different Container tabs. Keep different kinds of browsing far away from each other (for example, you might use one Container tab for managing your Checking Account and a different Container tab for searching for new songs by your favorite band) -
25
Tree Style Tab
Tree Style Tab, Show tabs like a tree.
This extension to Firefox provides the ability to work with tabs as "trees". New tabs opened from the current tab are automatically organized as "children" of the current tab. Such "branches" are easily folded (collapsed) by clicking on the arrow shown in the "parent" tab, so you no longer need to suffer from too many visible tabs. If you want, you can restructure the tree via drag and drop. Such a tree of tabs will behave like a visual browsing history for you. For example, if you see a list of search results for a topic, each search result link will open in new child tab. New tabs opened from these "child" tabs will appear as descendants of their originating tabs. You'll easily dig and dig deeply, without losing your browsing trail - if you want to go back to the original search result, you just have to switch to the "root" tab. Moreover, each tree will reflect a group of tabs on a similar topic.
