dashicons fail w3c css validation

[manuel_84]

/wp-includes/css/dashicons.min.css?ver=4.9.2

line 2: .dashicons, .dashicons-before:before

0 is not a value for transition : color 0.1s ease-in 0

[manuel_84]

fix by adding a "s" after the final 0:

transition : color 0.1s ease-in 0s

[GaryJ]

Thank you @manuel_84 for opening your first ticket :-)

Good catch with the bug.

An alternative solution would be to drop the transition-delay completely since the ​default is 0s anyway:

transition: color 0.1s ease-in;

[chetan200891]

Created patch to drop the transition-delay completely from dashicons.css

[SergeyBiryukov]

Per ​https://developer.mozilla.org/en-US/docs/Web/CSS/time:

Although unitless zero is allowed for <length>s, it's invalid for <time>s.

[SergeyBiryukov]

In 42689:

Administration: Remove erroneous transition-delay values from CSS files.

Although unitless zero is allowed for <length> CSS data type, it's invalid for <time> data type.

Props chetan200891, manuel_84, GaryJ.
Fixes #43195.

[SergeyBiryukov]

Created a GitHub issue for genericons.css: ​https://github.com/Automattic/Genericons/issues/109, since it's bundled with Twenty Fifteen and Twenty Sixteen.

[SergeyBiryukov]

#43769 was marked as a duplicate.

[desrosj]

#45559 was marked as a duplicate.

[swissspidy]

#46182 was marked as a duplicate.

[desrosj]

In 45097:

Administration: Remove unnecessary transition-delay values from Dashicons.

A unitless 0 value for a <time> CSS data type was reintroduced in [45040]. This is allowed for <length> data types, but is invalid for <time>.

See #43195.
Fixes #46774.