CSS -webkit-user-modify Property Reference

The CSS -webkit-user-modify property is a nonstandard property in WebKit Extensions. Review its formal syntax, computed behavior, and practical declarations.

Updated 2026-08-12

-webkit-user-modify overview

The CSS -webkit-user-modify property is a nonstandard property in WebKit Extensions. Review its formal syntax, computed behavior, and practical declarations.

The computed value normally inherits from the parent element when no declaration wins the cascade.

Syntax and formal definition

-webkit-user-modify formal syntax

Field	Value
Formal syntax	read-only \| read-write \| read-write-plaintext-only
Initial value	read-only
Applies to	allElements
Inherited	Yes
Percentages	no
Computed value	asSpecified
Animation type	discrete
Media	interactive
Specification group	WebKit Extensions
Status	Nonstandard

Practical examples

These declarations demonstrate valid ways to set -webkit-user-modify. The initial and inherit global keywords remain available even when a property-specific value is preferable.

-webkit-user-modify live example

CSS

.reset-example {
  -webkit-user-modify: initial;
}

.inherit-example {
  -webkit-user-modify: inherit;
}

@supports (-webkit-user-modify: initial) {
  .supported {
    -webkit-user-modify: initial;
  }
}