secret_password_lookupv blocks forever under flatpak

When running under both current Flatpak 3.38 and gnome-nightly runtimes, libsecret calls to secret_password_lookupv blocks forever, making Geary 100% unusable.

Currently, Geary is built under Flatpak with --talk-name=org.freedesktop.secrets enabled, since it also attempts to unlock the keying at startup (after getting bug reports that sometimes the keyring is locked at startup) and hence can't solely use libsecret's simple API.

If I disable the code that handles the unlocking at startup, then I can drop the talk-name arg, and secret_password_lookupv start working again.

Surely that method (and presumably the store equivalent, although that is untested) should work regardless of access to org.freedesktop.secrets when running under Flatpak?