A Dark Mode PDF Reader Competing with Adobe

I really could use a pdf reader that smartly cleans up scanned pdf's with gray backgrounds and not so sharp type. And images.

I sometimes use the "export" in Apple's Preview.app with the Quartz filters to darken or lighten. "Black" filter does a decent job of thresholding, but sometimes needs a prior lightening or darkening, since the Quartz filters are not adjustable.

And thresholding is mean to images. This should be well within the capability of non-AI software. If such exists, I may have ignored it due to sticker shock, "cloud only" or subscription fees. (Names withheld to protect the guilty. )

Open to suggestions, or consider this a suggestion.

I think some of the UI elements are not placed intuitively. The close file button should be on the top right side and the button to collapse the sidebar should be inside the sidebar (top left) and not next to it (when the sidebar is displayed of course).