Experimental CSS properties are typically implemented using vendor prefixes until the final behavior has been established and agreed upon. Most CSS3 properties have vendor-prefixed equivalents for multiple vendors, including Firefox (-moz-), Safari/Chrome (-webkit-) and Internet Explorer (-ms-). It's easy to forget to include the vendor prefixed version of a property when there are so many to keep track of.

This rule is intended to raise an issue when a vendor-prefixed property is missing. Note that only the following main vendors are checked by this rule:

• Firefox (-moz-)
• Safari/Chrome (-webkit-)
• Internet Explorer (-ms-)

Opera (-o-) for example is not.

The following properties have multiple vendor-prefixed versions:

Noncompliant Code Example

/* Noncompliant: Missing -ms- vendor-prefix */
.mybox {
  -webkit-hyphens: none;
  hyphens: none;
}

Compliant Solution

.mybox {
  -ms-hyphens: none;
  -webkit-hyphens: none;
  hyphens: none;
}