From our documentation (https://docs.opsmanager.mongodb.com/current/tutorial/configure-local-mode/#version-manifest and https://docs.opsmanager.mongodb.com/current/tutorial/configure-local-mode/), it's written:

In Local Mode:
        The version manifest must be downloaded and its contents copied and pasted into each Ops Manager server.
        You must update the version manifest as MongoDB, Inc. releases new versions.

Nowadays, OpsManager Manifest need to be updated in OpsManager directly. Also it tries to automatically retrieve the Manifest using a cross domain query through your browser, only if this query fail do we need to copy/paste the manifest.