https://github.com/popcorn-official/popcorn-desktop/releases/tag/v0.5.1
using Popcorn-Time-0.5.1-linux64-0.44.5.zip for codec support.
Install:
flatpak --user remote-add --if-not-exists flathub https://dl.flathub.org/repo/flathub.flatpakrepo
flatpak --user install org.gnome.Platform/x86_64/47
wget -c https://github.com/fastrizwaan/popcorntime-flatpak/releases/download/0.51/org.popcorntime.PopcornTime.flatpak
flatpak install --user org.popcorntime.PopcornTime.flatpak