G134 validating web pages
Drupal 8.4.0-alpha1 will be released the week of July 31, 2017, which means new developments and disruptive changes should now be targeted against the 8.5.x-dev branch.
Drupal 8.5.0-alpha1 will be released the week of January 17, 2018, which means new developments and disruptive changes should now be targeted against the 8.6.x-dev branch.
The important thing is if you want to validate your CSS style sheet embedded in an (X)HTML document, you should first check that the (X)HTML you use is valid.
Check links and anchors in Web pages or full Web sites.
Just like a minor negligence while constructing a building can cost life of millions of residents , the same way a small error left unnoticed can prove to be fatal for your website.
Therefore, this implies that we must run our website through all necessary tests.
So make it sure that you go through this post and run all the necessary tests on your website before making it live.
Just give the URL of your page and Watson will get a copy of it directly from the web server.This is the W3C Feed Validation Service, a free service that checks the syntax of Atom or RSS feeds.You can validate by URL or Validate by direct input.In content implemented using markup languages, elements have complete start and end tags, elements are nested according to their specifications, elements do not contain duplicate attributes, and any IDs are unique, except where the specifications allow these features.
(Level A)For all user interface components (including but not limited to: form elements, links and components generated by scripts), the name and role can be programmatically determined; states, properties, and values that can be set by the user can be programmatically set; and notification of changes to these items is available to user agents, including assistive technologies.A Web Page is mobile OK when it passes all the tests. The WDG HTML Validator is similar in many ways to the W3C HTML Validation Service.