Okular PDF reader from KDE is also available for Windows. It's FOSS. https://okular.kde.org/download/ https://okular.kde.org/download/ Edit: Wow I didn't know

Okular PDF reader from KDE is also available for Windows. It's FOSS. https://okular.kde.org/download/ https://okular.kde.org/download/ Edit: Wow I didn't know that SumatraPDF Reader is also FOSS. Awesome!