Extensions for w3.org
10 browser extensions built for w3.org. Compare features, permissions, and safety across Chrome, Firefox, and Edge.
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OnlineSIM Access
This extension is intended to provide unrestricted access to the onlinesim.ru website from anywhere in the world, regardless of location or Internet provider.
4.0—
Chrome Web StoreW3C Markup Validation Service for CSR pages
W3C Validator for client side rendering pages
Edge Add-onsW3C Markup Validation Service for CSR pages
W3C Validator for client side rendering pages
Chrome Web StoreBrawl Stars Extension
A Chrome-extension for Brawl Stars-fans
Chrome Web StoreCount the Days
Create and manage countdown timers with a start and end date.
Chrome Web StoreValidify
Validate HTML of the current page against W3C standards. View results in DevTools console or in the Validify Panel
Chrome Web StoreW3C Validator Errors
Checking the web page HTML validity using the validator.w3.org validation api
Chrome Web StoreRocket Validator HTML Guides
Adds links to HTML validation guides next to each issue in the W3C Validator and validator.nu.
Chrome Web StoreHelpMeApply - Auto Apply for Jobs, AI Job Search & Application Assistant
Auto apply to jobs, find AI-matched opportunities, complete applications faster and spend less time job hunting with HelpMeApply.