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13,255 extensions found in Web Development

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  • Scientific Calculator

    Scientific Calculator

    Scientific Calculator for Firefox

    FirstScienceCalc

    89 users

  • Script Switch

    Script Switch

    Quickly enable or disable javascript for all tabs and windows with a convenient button and keyboard shortcut.

    Jordan Majd

    89 users

  • close tab right click

    close tab right click

    Close tab from right click context menu.

    kakakikikeke

    89 users

  • cookie.txt

    cookie.txt

    Exports your cookies super fast in a format compatible with wget

    Yifei Wang

    89 users

  • MDN Web Docs Search

    MDN Web Docs Search

    Adds MDN Web Docs as a search option.

    Danny Bowen

    89 users

  • SpellCheckAnywhere

    SpellCheckAnywhere

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

    cisco211

    89 users

  • PlePer Tools - Open Google Maps from SERP KG

    PlePer Tools - Open Google Maps from SERP KG

    PlePer Tools - Open Google Maps from SERP Knowledge Graph

    Stan Kolev

    89 users

  • CodeX

    CodeX

    CodeX aims to be a lightweight browser extension that provides an easy and convenient way to search for plagiarism on GitHub.

    Anthony

    88 users

  • Twitch Username and User ID

    Twitch Username and User ID

    Fetch user id of a Twitch username or the username of a Twitch user id. The Firefox port of https://chrome.google.com/webstore/detail/twitch-username-and-user/laonpoebfalkjijglbjbnkfndibbcoon

    swiftyspiffy

    88 users

  • RTL for AI Sites

    RTL for AI Sites

    Smart right-to-left for AI sites like Claude, ChatGPT, Gemini, Grok, DeepSeek, Perplexity, Copilot, Poe and Arena.

    Arman Babaei

    88 users

  • Color Picker - Modern & Sleek

    Color Picker - Modern & Sleek

    Color Picker - Modern & Sleek lets you identify and copy colors from any webpage. View all colors used, select and copy them in HEX or RGB format with a sleek, user-friendly interface. Ideal for designers and developers needing accurate color codes.

    Vivek Parmar

    88 users

  • BugzillaJS - Tweaks for Bugzilla

    BugzillaJS - Tweaks for Bugzilla

    BugzillaJS adds a number of features to Mozilla's Bugzilla. Keyboard shortcuts, quick file links, inline image/github previews, gravatars and more.

    Gregory Koberger

    88 users

  • Leet Xt - Supercharge your Leetcode practice

    Leet Xt - Supercharge your Leetcode practice

    Supercharge your LeetCode practice - Add to Friends, Premium Features, per Contest Friends Rating, and more!

    binbard

    88 users

  • Switch Tabs

    Switch Tabs

    Switch tabs every x seconds.

    Ph4nToM00

    88 users

  • Ollama Web Extension

    Ollama Web Extension

    Securely connect your locally hosted Ollama LLM to websites you trust. This extension exposes a simple API (window.ollama) to supported sites, enabling them to connect to your Ollama instance — without sending any data to the cloud.

    Abhay

    87 users

  • Screenshot.rocks: One-click design mockups

    Screenshot.rocks: One-click design mockups

    Create beautiful browser and mobile mockups in one-click.

    Dave Earley

    87 users

  • Unix Time Converter

    Unix Time Converter

    Converts Unix time to human readable format and vice versa

    Renato Massone

    87 users

  • Youtube Overlay Remover

    Youtube Overlay Remover

    Toggle for hiding the youtube.com's HTML5 player overlay, that blocks vision at the top and bottom of the video when moving the mouse or pausing, in and out of full screen. Use Shift+Alt+X as default shortcut, or change it in the Extensions Manager.

    onekanaka

    87 users

  • Short URL Expander

    Short URL Expander

    Adds an Expand Shortened URLs item to the context menu. Links on the page that contain shortened URLs will be resolved and replaced with their final URL.

    James Mazikowski

    87 users

  • Dungeon Extension v2

    Dungeon Extension v2

    Enhance AI Dungeon with visuals, audio effects, and text formatting

    clauds-clauds

    87 users

  • falsh

    falsh

    Modify the navigator.platform while simulating a mobile viewport

    123

    86 users

  • TagCheck

    TagCheck

    Lists usage of Universal Analytics, Google Analytics 4, and Google Tag Manager on a page.

    embeddedt

    86 users

  • Github Whitespace Disabler

    Github Whitespace Disabler

    Force Github "Files Changed" tab on Pull Requests to hide whitespace changes when showing diffs.

    Oliver Maksimovic

    86 users

  • server-spy2

    server-spy2

    1. show server headers、ip. 2. show an QR code for others devices to scan.

    马云腾

    85 users

  • GrabzIt Web Scraping Assistant

    GrabzIt Web Scraping Assistant

    Create Web Scrapes online easier than ever before with GrabzIt’s Web Scraping Assistant.

    GrabzIt

    85 users