Does this app download and run (nonfree or untrusted) software from servers at runtime?

[JacobKfromIRC]

Based on the readme, wiki, and reading the source code, it seems like the answer is yes, but I'm not completely sure. I see webkit_web_view_load_uri(*this, WHATSAPP_WEB_URI); in the source code, and it looks like running JavaScript is the default, so I think this app is downloading the nonfree WhatsApp browser app and running it. Is that true?

Part of the reason why I ask is that it looks like this app is in PureOS's flatpak repo but I think it probably shouldn't be if it is running nonfree software.