linear-gradient to keyword conversion error

[yisibl]

input

.foo {
    background: linear-gradient(to right, red, green);
}

output

playground

.foo {
  background: -webkit-linear-gradient(right, red, green); /* The directions of the old and new grammars are not equivalent. */
  background: linear-gradient(to right, red, green);
}

expected

.foo {
  background: -webkit-linear-gradient(left, red, green);
  background: linear-gradient(to right, red, green);
}

https://developer.mozilla.org/en-US/docs/Web/CSS/gradient/linear-gradient#browser_compatibility