Death of CSS vendor prefix

@ CSS

Do you remember browser engine prefixes?

-webkit-transition: all 4s ease;
-moz-transition: all 4s ease;
-ms-transition: all 4s ease;
-o-transition: all 4s ease;
transition: all 4s ease;

These are typically prefix syntaxes added before certain experimental, non-standard CSS features, such as:

  • -webkit- (Chrome, Safari, newer versions of Opera and Edge, almost all browsers on iOS including iOS for Firefox, basically all WebKit or Chromium-based browser engines)
  • -moz- (Firefox)
  • -o- (old versions of Opera)
  • -ms- (Internet Explorer and Microsoft Edge before using Chromium base)

These prefixes were meant to allow developers to implement new CSS features before official browser support, and at that time, it was common to use PostCSS-like preprocessors’ autoprefixer🔗 plugin to preprocess CSS and add these prefixes, enabling website syntax to adapt to a broader user base.

However, recently, the number of properties requiring prefixes has been declining sharply, and it is highly likely that no new prefixes will be added in the future.

Why are browser prefixes gradually disappearing?

The reason is that the testing prefixes have deviated from their original purpose — functional experimentation.

As the number of prefixes increased, things became more chaotic. Browser vendors gradually recognized that an excess of experimental prefixes could lead developers to rely on non-standardized features, thereby affecting website compatibility across different browsers.

Therefore, modern browsers are more cautious about introducing experimental features, ensuring that new functionalities have sufficient completeness and cross-browser consistency before introduction, and gradually moving away from using browser engine prefixes to test new features. Instead, they are using manual toggles in browser settings or providing test versions of browsers (Chrome Canary🔗, Firefox Nightly🔗) for experimental purposes.

Conclusion

The web is moving towards a more consistent and standardized direction, which is good news for developers!

Further Reading