{"action":"created","issue":{"url":"https://api.github.com/repos/whatwg/html/issues/3672","repository_url":"https://api.github.com/repos/whatwg/html","labels_url":"https://api.github.com/repos/whatwg/html/issues/3672/labels{/name}","comments_url":"https://api.github.com/repos/whatwg/html/issues/3672/comments","events_url":"https://api.github.com/repos/whatwg/html/issues/3672/events","html_url":"https://github.com/whatwg/html/issues/3672","id":321088466,"number":3672,"title":"Proposal: a non-render-blocking way to load stylesheets","user":{"login":"iamakulov","id":2953267,"avatar_url":"https://avatars0.githubusercontent.com/u/2953267?v=4","gravatar_id":"","url":"https://api.github.com/users/iamakulov","html_url":"https://github.com/iamakulov","followers_url":"https://api.github.com/users/iamakulov/followers","following_url":"https://api.github.com/users/iamakulov/following{/other_user}","gists_url":"https://api.github.com/users/iamakulov/gists{/gist_id}","starred_url":"https://api.github.com/users/iamakulov/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/iamakulov/subscriptions","organizations_url":"https://api.github.com/users/iamakulov/orgs","repos_url":"https://api.github.com/users/iamakulov/repos","events_url":"https://api.github.com/users/iamakulov/events{/privacy}","received_events_url":"https://api.github.com/users/iamakulov/received_events","type":"User","site_admin":false},"labels":[{"id":255178143,"url":"https://api.github.com/repos/whatwg/html/labels/addition/proposal","name":"addition/proposal","color":"d4c5f9","default":false},{"id":683118858,"url":"https://api.github.com/repos/whatwg/html/labels/topic:%20style","name":"topic: style","color":"009800","default":false}],"state":"open","locked":false,"assignee":null,"assignees":[],"milestone":null,"comments":5,"created_at":"2018-05-08T08:22:43Z","updated_at":"2018-05-08T09:50:59Z","closed_at":null,"author_association":"NONE","body":"Proposal: let’s have something like\r\n\r\n```html\r\n<link rel=\"stylesheet\" href=\"...\" async />\r\n```\r\n\r\nfor loading and applying stylesheets without blocking the page rendering.\r\n\r\n**User story**\r\nI, as an application developer who cares about performance, want to have a non-render-blocking way to load non-critical CSS.\r\n\r\n[Critical CSS](https://www.smashingmagazine.com/2015/08/understanding-critical-css/) is the part of site styles that are required for the very first rendering. This could be e.g. CSS for above-the-fold content. Non-critical CSS is the remaining styles.\r\n\r\n**Specific use cases**\r\n\r\n* In a news site: load and apply styles for the page layout and the news content + hide the comments/ads blocks. Then, without blocking the initial rendering, load and apply styles for comments and ads.\r\n\r\n* On a landing: load and apply styles for above-the-fold content + hide the content below the fold. Then, without blocking the initial rendering, load and apply styles for below-the-fold stuff."},"comment":{"url":"https://api.github.com/repos/whatwg/html/issues/comments/387348603","html_url":"https://github.com/whatwg/html/issues/3672#issuecomment-387348603","issue_url":"https://api.github.com/repos/whatwg/html/issues/3672","id":387348603,"user":{"login":"SilentImp","id":217308,"avatar_url":"https://avatars0.githubusercontent.com/u/217308?v=4","gravatar_id":"","url":"https://api.github.com/users/SilentImp","html_url":"https://github.com/SilentImp","followers_url":"https://api.github.com/users/SilentImp/followers","following_url":"https://api.github.com/users/SilentImp/following{/other_user}","gists_url":"https://api.github.com/users/SilentImp/gists{/gist_id}","starred_url":"https://api.github.com/users/SilentImp/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/SilentImp/subscriptions","organizations_url":"https://api.github.com/users/SilentImp/orgs","repos_url":"https://api.github.com/users/SilentImp/repos","events_url":"https://api.github.com/users/SilentImp/events{/privacy}","received_events_url":"https://api.github.com/users/SilentImp/received_events","type":"User","site_admin":false},"created_at":"2018-05-08T09:50:59Z","updated_at":"2018-05-08T09:50:59Z","author_association":"NONE","body":"@montogeek main idea — don't use js and use only one styles definition. Actually idea is quite good."}}
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