CSS

Preload

(async fonts, styles, scripts ..etc)

Preloading means downloading asynchronously before use, so rendering won't be blocked. Later when required we can add that link to dom.

In following example , link is preloaded & later on some condition (here onload of that link itself)adding that link to dom ( setting proper attribute to make it apply on the browser)

<link href="/static_hosted/common_md.css" rel="preload"
as="style" onload="this.rel = 'stylesheet'"
onerror="this.onerror=null;this.href='/learning/static_hosted/common_md.css';"/>

Note : Link can be of any type like script, fonts, videos..etc

Grid & flex bugs

https://github.com/rachelandrew/gridbugs https://github.com/philipwalton/flexbugs

White space

Shapes/ Clip Paths