I don't know if this was added because of this comment, but the list does include poles:

> The majority of Stolpersteine commemorate Jewish victims of the Holocaust. Others have been placed for Sinti and Romani people (then also called "gypsies"), Poles, homosexuals, [...]

Edit: It looks like the word Poles was added today, so I assume it's because of this comment (otherwise that's a pretty wild coincidence.)