I’m not sure about the copyright legalities involved with making/distributing a pre-built flatpak app containing Citrix code. So you’ll have to build it yourself, but don’t worry, it should be pretty easy with the instructions I’ve provided.
Do the commands listed in the readme on the github page not work? I don’t know much about Fedora/Silverblue but I would have assumed the steps to build and install would be the same as any other distro.
Do we have more information on that? Could it be integrated in Flathub directly? Is the “HDX RealTime Media Engine for Skype” needed for Citrix to work? (it could be made an extension)