Disallow outline clearing.
Why? Because
Sources:
The following pattern is considered a violation:
.foo:focus {
outline: 0;
}.bar:focus {
outline: none;
}.baz:focus {
outline: none;
border: transparent;
}.quux {
.quuux:focus {
outline: 0;
}
}The following patterns are not considered violations:
.foo {
outline: 0;
}$primary-color: #333;
.bar:focus {
outline: 1px solid $primary-color;
}.baz:focus {
outline: 1px solid #333;
}.quux:focus {
outline: 0;
border: 1px solid #000;
}Similar rule is in Stylelint, but it triggers another error message and does not check for :focus selector and border property.
{
"declaration-property-value-blacklist": {
"outline": ["none", "0"]
}
}