Cabin Filter Recommendation Needed

Pulled open the cabin filter door (as per other posts, it is tough to access), and no filter was present. What was present was lots of nature (leaves,etc.), and even some man-made plastic (car wash vacuum to the rescue). As the owner's manual notes, this filter is not necessary (though the air will not be filtered). Is the white door even needed? Sure, the ideal would be a filter with regular replacement, but considering the difficulty involved maybe the route to take is just open up the system (no filter, no white door), and experience all the "great outdoors" has to offer.

Keep the white door. Otherwise, a lot of your air flow will come out of that hole instead of the directed vents and openings.

Every season, open the white door and turn your fan on high to blow debris out.

I kept the filter in my 99 PA.