The example given in the manual of backend_secret_service was triggering an error with message "Error: attempt to apply non-function" due to calling kb$create_keyring instead of calling kb$keyring_create. Fixing the example by calling the latter does not solve the issue. Hence, I replace create_keyring with keyring_create in the manual, on R side, and on C side. Now it works without errors.
The example given in the manual of backend_secret_service was triggering an error with message "Error: attempt to apply non-function" due to calling kb$create_keyring instead of calling kb$keyring_create. Fixing the example by calling the latter does not solve the issue. Hence, I replace create_keyring with keyring_create in the manual, on R side, and on C side. Now it works without errors.