This app seriously needs to be updated or removed from Flathub. It’s a shame too, because this is (was) the best podcast app on Linux in my opinion.
Fortunately, Arch Linux and Opensuse include a patched version in their repos that works pretty well, and the Opensuse rpm seems to work on Fedora. I just cannot understand how an app which simply does not work (crashes upon adding a podcast subscription) is allowed to be on flathub after years.