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Vendor Prefix Without Standard Property

Vendor prefixes (-webkit-, -moz-, -ms-) were used for experimental CSS features. When a feature becomes standard, you should include the unprefixed version as well. Using only the prefixed version means your CSS only works in specific browsers.

Why It Matters

A -webkit- only property works in Chrome and Safari but fails in Firefox. Most modern CSS properties no longer need prefixes, so using them alone is often unnecessary clutter.

Code Examples

Bad CSS
.box {
  -webkit-border-radius: 8px;
  -moz-border-radius: 8px;
  /* missing standard property */

  -webkit-transition: all 0.3s;
  /* missing standard property */
}
Good CSS
.box {
  border-radius: 8px;      /* no prefix needed since 2012 */
  transition: all 0.3s;    /* no prefix needed since 2013 */
}

/* Only use prefixes when actually needed: */
.scroll {
  -webkit-overflow-scrolling: touch; /* still iOS-only */
}

How to Fix

  • 1Always include the standard (unprefixed) property AFTER the prefixed versions.
  • 2Most properties no longer need prefixes: border-radius, transition, transform, flexbox, grid.
  • 3Use Autoprefixer in your build process to add necessary prefixes automatically.
  • 4Check caniuse.com to see if a prefix is still needed for your browser targets.

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