PDF output separation preview

Dear #GIMP #INKSCAPE #SCRIBUS #TEX #LATEX and #PDF #opensource and #freesoftware lovers...

Do you know any #foss / #floss application that can preview output separation on a PDF file like Adobe Acrobat pro does?

I have been tried hard, even using javascript with #pdfjs but I couldn't find something very suitable for doing #prepress with opensource.

I am also ok with any #web applications.

Thanks... 🙏