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9,699 extensions found in Web Development

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  • User-Agent Switcher PRO

    User-Agent Switcher PRO

    Anonymize your browsing by easily switch/spoof/fake User-Agent with what you want. User-Agent selection mode: Manual, Auto, Random

    Matt Glow

    58 users

  • BarnumPT

    BarnumPT

    Step right up to BarnumPT—your ultimate digital marketing ringmaster! Perfect for ClickFunnels users and savvy marketers.

    Prime Mover

    58 users

  • RTL for Deepseek

    RTL for Deepseek

    Toggle RTL direction on chat.deepseek.com and change icon based on state.

    diako hamidian

    58 users

  • User Agent Masquerade

    User Agent Masquerade

    Adds a button to the toolbar to switch the User-Agent header.

    Nobuyuki Honda

    58 users

  • ABC JS-CSS Injector

    ABC JS-CSS Injector

    A injector extension for Firefox users.

    ABCeLearning

    58 users

  • SpellCheckAnywhere

    SpellCheckAnywhere

    This extension allows you to make spellcheck work on whole page body.

    cisco211

    58 users

  • Lexical Developer Tools

    Lexical Developer Tools

    Adds Lexical debugging tools to the Firefox Developer Tools. It allows you to inspect the Lexical state in the Firefox Developer Tools.

    Lexical

    58 users

  • WikimediaDebug

    WikimediaDebug

    Control the X-Wikimedia-Debug header on HTTP requests.

    Timo Tijhof

    58 users

  • KOSHIAN delフォームをポップアップで開く

    KOSHIAN delフォームをポップアップで開く

    delフォームをポップアップで開きます

    Pachira

    57 users

  • Google Search Enhancer

    Google Search Enhancer

    Google Search Enhancer is a Firefox addon that optimizes the Google search experience for mobile and tablet users. By adjusting the user-agent string, it aligns Firefox's functionality with that of Chrome, delivering a seamless and improved search.

    Dr. B. R. Shriradhakrishnasharnam

    57 users

  • Logify - Parental Control

    Logify - Parental Control

    fully integrated with Logify Apps

    Logify

    57 users

  • Tally-Ho!

    Tally-Ho!

    A simple tally counter for the browser.

    brainfoam

    57 users

  • Alt Text Display

    Alt Text Display

    Add a context menu to images to show their URL and alt text

    codepo8

    57 users

  • Toggle CSS outline

    Toggle CSS outline

    Simple extension that toggles a red outline around all elements in a page on/off, useful for CSS debugging.

    theodejager

    57 users

  • Remove X-Frame-Options Header

    Remove X-Frame-Options Header

    Removes the X-Frame-Options header from all responses.

    Callaghan

    57 users

  • PixelGrid

    PixelGrid

    The tool to overlap your website layout with a grid.

    Sergey Zwezdin

    57 users

  • Tracked for Basecamp

    Tracked for Basecamp

    Kanban boards, labels, and estimates all within Basecamp.

    TrackedHQ

    57 users

  • ClipboardX

    ClipboardX

    ClipboardX is a simple clipboard manager for Firefox. It organizes and edits your copied content across 10 clear categories. Right-click options and secure storage make copy and paste tasks faster and easier

    Mohamed Afsar J

    56 users

  • SubsNet SyncCookie

    SubsNet SyncCookie

    A Firefox extension to synchronize cookies.

    SubsNet

    56 users

  • Whiteboard Pro – Draw On Any Site

    Whiteboard Pro – Draw On Any Site

    Turn any webpage into a whiteboard! Draw freehand, create lines, and customize thickness, opacity, and colors. Works on any site with full-page coverage. Perfect for notes, brainstorming, and teaching—fast, lightweight, and privacy-friendly. 🚀

    moeez

    56 users

  • CORS for Me

    CORS for Me

    Allow cross-domain xhr request by adding CORS headers to response. Works on Android as well as on PC. HTTPレスポンスにCORSヘッダを追加してクロスドメインのxhrリクエストを許可する拡張機能。Androidでも機能します

    yobukodori

    56 users

  • PHP Documentation Search

    PHP Documentation Search

    This add-on searches the official php documentation for a given term. It provides a search field, that can be accessed from the toolbar as well as it adds a search option for selected text to the context menu.

    Firefox user 13918004

    56 users

  • Repomix

    Repomix

    Add a button to quickly access Repomix from GitHub repositories

    yamadashy

    56 users

  • Asuka.IO Whois - Domain Name Lookup Tool

    Asuka.IO Whois - Domain Name Lookup Tool

    This extension allows you to lookup the domain name information easily. By clicking the addon button or selecting from the context menu, you can display the domain name registration information of the site you are currently browsing.

    Asuka.Net

    55 users

  • Excalibur Dev Tools

    Excalibur Dev Tools

    Excalibur.js browser plugin for debugging your games

    Erik Onarheim

    55 users