This older post also had similar behavior when downloading from Jottacloud (hangs on Get), so maybe it is a more general problem (Jottacloud also uses OAuthHelper):
Okay, some log entries:
8 Jun 2023 20:27: Backend event: Get - Started: duplicati-20230606T020000Z.dlist.zip.aes (36.30 MB)
8 Jun 2023 20:27: Backend event: Get - Completed: duplicati-20230321T020000Z.dlist.zip.aes (36.28 MB)
8 Jun 2023 20:26: Backend event: Get - Started: duplicati-20230321T020000Z.dlist.zip.aes (36.28 MB)
8 Jun 2023 20:26: Backend event: Get - Completed: duplicati-20220910T102949Z.dlist.zip.aes (33.26 MB)
8 Jun 2023 20:26: Backend event: Get - Started: duplicati-20220910T1029…