Browserling - Cross-browser testing
Cross-browser test websites in the most popular browsers such as Internet Explorer, Edge, Chrome, Firefox, Safari and Opera. Try for free!
Firebug Lite for Opera 15+
Custom Style Script
Click on any HTML element to get the font info in a popup
Live editor for CSS and LESS - Magic CSS
Live preview of CSS/LESS code with an in-page editor. Autocomplete, convert LESS to CSS, beautify, minify, CSS reloader, linter, ...
Right Click Validator
Right click on any webpage to validate it using the W3 NUValidator service.
Code tree for GitHub
PDF API HTML5
Use Redux DevTools in the DevTools
Modify Header Value
Add, modify or remove a header for any request on desired domains.
Browse JSON like you do it in Finder.
Определение CMS - iTrack
Расширение для определения CMS сайта
Corser - Authorize CORS requests
Cross-browser extension for authorizing cross-origin resource sharing (CORS) requests. This extension can be installed on browsers supporting the WebExtensions API (https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions) It intercepts all CORS requests and responses headers, and records/adds/changes their values so as to authorized unauthorized CORS requests. Use this extension only for testing purposes
OctoLinker is the easiest and best way to navigate between files and projects on GitHub.com. Files containing the following keywords will now have links that redirect you either to the relative file or to the projects GitHub page. Depending on the value, it may redirect you to an external website like a manual page or another service.
Zend Debugger Toolbar
Provides integration with Zend debugging and profiling tools.
A webpage form filler that populates context specific random test data into forms elements.
This extension allows you to add your own custom website specific CSS style sheets.
Get Thumbnails or Image to video YouTube
Make thumbnail previews or images from YouTube videos
Edit the Page
Toggles the 'Design Mode' so that you can edit the contents of the page.
Shows the response times and uptime of a desired server. Useful to see how performs internet or a wireless access point.
Remove cookie(s) for the current domain
Remove cookie(s) for the current site with just one click
W3C Markup Validation Service
This validator checks the markup validity of Web documents in HTML, XHTML, SMIL, MathML, etc.
Website Color Changer
Extends the Developer Tools, adding a sidebar for colors manipulation
Website Analysis & SEO Tool
Website SEO audit tool that provides website analysis in SEO, performance, validity, security, accessibility and other criteria.
SEO TOOLS - YATEO
Opens all the essential tools for SEO in one click.
Hitsteps Visitor Manager
Get your website analytics insight and get notified about updates and live support requests in your dashboard
View all HTTP Requests and Responses sent between the Web browser and the Web server.
Flag & WHOIS SEO Domain Full Info
Return the domain's IP address , information about security, localization of server, ping, etc.
Quickly view the HTTP headers of the current tab.
Edit with Adobe Photoshop
Adds a context menu item to send image links directly to Adobe Photoshop photo editor