:placeholder-shown is replaced with -moz-placeholder, although this is outdated

Due to a change in autoprefixer in the last two weeks I assume, suddenly :placeholder-shown is replaced with :-moz-placeholder. According to caniuse, this should only be necessary in Firefox < 50, not in current versions.

Although as far as I understand, :-moz-placeholder should be a synonym to ::placeholder, i.e. to style the placeholder, whereas :placeholder-shown is an indicator if the placeholder is visible or not. So if the focus is within the input and the placeholder text disappears, :placeholder-shown is false. That's something different than styling the placeholder.

Our .browserslistrc looks like this, so Firefox < 50 should not be relevant:

> 1% in DE
last 2 versions
not dead

For the time being, I disabled replacement of :placeholder-shown with /* autoprefixer: ignore next */.