This is a fork of the com.slack.Slack Flatpak manifest with the extra data removed and embedded like a regular Flatpak.
The output of the build can be installed offline or packaged without any online dependencies.
Because Slack does not want the Electron client to be redistributed, Flatpak from this manifest cannot be made available publicly, but you can always build your own for offline installation. This is not legal advice, please check with your legal counsel.