We are trying to understand detailed usage observation of Topics API, and seems even from Networking tab, there is a call sent and caught, within chrome://topics-internals/ there is no observer recorded, is this expected?

When using the HTTP header mechanism to interact with the Topics API, the topics are sent in the Sec-Browsing-Topics request header, but they are only observed if the server replies with the Observe-Browsing-Topics: ?1 response header. See all the details in this part of the explainer.

A quick note is that as suggested we will add more details into our account to ensure there is no concern from your side, but if it is not required we would prefer it to be totally open-sourced eco-system:)

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