[Fixed] Adding a 'mailing list' filter

I am trying to create a filter within Proton Mail, that adds a label 'mailing list' whenever Proton marks an email as from a mailing list.

It doesn't seem so easily possible as far as i can tell and I don't have the time (or will at the moment) to try and create it with a Sieve filter.

Is there an easy way to do this?