Today CSS Custom Properties are supported in all the major browsers.
Now it’s time to do the next step- to have an ability to register new Custom Properties from JavaScript and setup the browser how to work with them (e.g. real CSS polyfills). They should work with the same performance as the native CSS properties, being animatable and aligned with CSSOM.
Custom Properties can be used as a bridge between CSS and JavaScript. Houdini Task force introduces specs and JavaScript Worklets to expose the interaction with previously fully internal browser rendering mechanisms (during Paint, Layout, Composite stages).
All this brings Front-End development to the next level, parts of which are already available for the developers.
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