BuiltWith Technology Profiler
Find out what the website you are visiting is built with using this extension.
GitHub on steroids
Click on any HTML element to get the font info in a popup
PDF API HTML5
Modify Header Value
Add, modify or remove a header for any request on desired domains.
Live HTTP Headers
Monitor all HTTP/HTTPs traffic from your browser.
View all HTTP Requests and Responses sent between the Web browser and the Web server.
Use Redux DevTools in the DevTools
Edit the Page
Toggles the 'Design Mode' so that you can edit the contents of the page.
Browse JSON like you do it in Finder.
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, ...
WordPress Theme and Plugins Detector
This tool detects theme and plugins used on WordPress sites and displays information about them.
This extension allows you to add your own custom website specific CSS style sheets.
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!
ChroPath for Opera
AutonomIQ offers a developers platform ChroPath to generate and validate unique selectors like relative xpath with iframe support
The simplest extension for working with web fonts
Quickly view the HTTP headers of the current tab.
OCR - Image Reader
A powerful optical character recognition (OCR) extension to capture and convert images to text
Right Click Validator
Right click on any webpage to validate it using the W3 NUValidator service.
Picture in Play
Indicates whether the `picture` element is in use on a page.
Website Color Changer
Extends the Developer Tools, adding a sidebar for colors manipulation
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
This will take the URL of the current tab and send it to PageSpeed Insights for a web performance analysis.
Google Analytics Debugger
A browser extension for debugging Google Analytics tracking code
Web Developer Checklist
Analyses any web page for violations of best practices
SEO Analysis with Seoptimer
Just one click to SEO Analysis with Seoptimer
Flag & WHOIS SEO Domain Full Info
Return the domain's IP address , information about security, localization of server, ping, etc.
Shows the response times and uptime of a desired server. Useful to see how performs internet or a wireless access point.
Edit with Adobe Photoshop
Adds a context menu item to send image links directly to Adobe Photoshop photo editor