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13,237 extensions found in Web Development

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  • Speed Test Pro

    Speed Test Pro

    Measure your internet speed (ping, download, upload) with 1 click, 100% client-side in your browser. No external APIs or services required. Uses Cloudflare’s public endpoints for accurate multi-stream testing. Export history as timestamped JSON.

    Libor Benes (Dr. B)

    3 users

  • RunCode - OnlineCompiler

    RunCode - OnlineCompiler

    Online compiler supporting 9 languages to run your basic code to learn or teach.

    RunCode - Cloud Development Environment

    3 users

  • Proxy-solutions settings

    Proxy-solutions settings

    PSs (Proxy-solutions settings) - это удобный инструмент для настройки и управления прокси в браузере.

    Proxy-solutions

    3 users

  • SEO Analyser

    SEO Analyser

    Instant SEO analysis and scoring for any webpage with real-time feedback

    Todacu

    3 users

  • AI Chat Broadcaster

    AI Chat Broadcaster

    AI Chat Broadcaster is a browser extension enabling users to send identical prompts to multiple AI chat platforms simultaneously. Key features include: Multi-platform broadcasting (ChatGPT, Claude, Grok, DeepSeek, Mistral). Selective sending

    Ruslanlap

    3 users

  • Copy body.innerHTML

    Copy body.innerHTML

    Adds a context menu option to copy a document's body.innerHTML.

    goon

    3 users

  • PageLoaded

    PageLoaded

    Signals via DOM in the clipboard when a html page has been loaded.

    Mel N Farmer

    3 users

  • Auto Suspend Tabs

    Auto Suspend Tabs

    Reduce RAM usage by automatically suspending background tabs.

    Beard

    3 users

  • WebLabeler

    WebLabeler

    WebLabeler helps you visually label websites and browser tabs by environment (dev, test, staging, prod). Customize labels, favicon badges, and domain rules to quickly distinguish tabs and avoid working in the wrong environment.

    nfdff

    3 users

  • Rainbow Delimiters

    Rainbow Delimiters

    A web browser plugin to colorize the matched brackets of source code on HTML pages

    Yanying Wang

    3 users

  • PX to REM Converter

    PX to REM Converter

    Converts pixel (px) to rem and vice versa

    CSS Unit Converter

    3 users

  • App Notification No more

    App Notification No more

    Removes the annoying 'add x as app for y' notifications

    adioe3

    3 users

  • Checka11y.css

    Checka11y.css

    This browser extension allows you to use Checka11y.css directly in your browser. Just simply toggle Checka11y.css on & off to see the accessibility issues highlighted instantly.

    Jack Domleo

    3 users

  • Microsoft Bing

    Microsoft Bing

    (Unofficial) Use Bing right in a browser. This is an extension where you can use Bing in an extension, you don't need to open a new tab.

    Moses

    3 users

  • HTTP Headers Customize

    HTTP Headers Customize

    'HTTP Headers Customize' extension rewrite http headers based on a rules.

    fumidzuki

    3 users

  • Hunter Helper

    Hunter Helper

    Encoding/decoding, hashing, JWT, timestamp, and utility tools for bug bounty hunters. Features a Burp-style chained decoder, smart decode, and more.

    paa

    3 users

  • Barcode scanner emulator

    Barcode scanner emulator

    Emulates the input of a barcode scanner line

    Deneiz

    3 users

  • Dive Scope

    Dive Scope

    HTML measurement

    DiveScope

    3 users

  • Custom Style Manager

    Custom Style Manager

    Custom Style Manager allows domain-level CSS styling for any website you visit. Your changes will sync across all of your logged-in Firefox browsers.

    Halil Can

    3 users

  • seochaxun

    seochaxun

    查询当前网站的详细信息，包括流量、关键词、服务器、备案等详细信息。中国站长必备工具。

    惆怅的老李

    3 users

  • Forgejo Notifier

    Forgejo Notifier

    Get notifications for your Forgejo pull requests

    Jasmin Aljic

    3 users

  • Checky - Contrast Checker

    Checky - Contrast Checker

    Check WCAG colour contrast between two colours

    mihai

    3 users

  • JSON Bonsai

    JSON Bonsai

    Beautiful JSON viewer: interactive tree, JMESPath queries, search, schema inference, and base16 theming with 13 bundled themes.

    hackslashdash

    3 users

  • Coconut Shell

    Coconut Shell

    A Firefox extension that allows you to encrypt messages before sending them on any website. Just select the text you want to encrypt, right-click, and select 'Encrypt'. You can also decrypt messages by selecting the text and selecting 'Decrypt'

    skh

    3 users

  • Kronos Timer

    Kronos Timer

    Simple tool for tracking your working time.

    Nikola Markovic

    3 users