Google claims it recently found un-named third-party Chromium-based browsers integrating Google cloud-based features, such as Chrome sync and Click to Call, that were intended only for Google Chrome users. In other words, This meant that a small fraction of users could sign into their Google Account and store their personal Chrome sync data, such as bookmarks, not just with Google Chrome, but also with some third-party Chromium-based browsers.
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Google was not amused.
Starting on March 15th, Google said it will limit access to many Chrome application programming interfaces (API) inside Chromium starting March 15, 2021. This means users using the Chromium web browser or any other web browser based on its open-source codebase won t be able to use most Google-specific API-enabled services. This includes the ability to sync Chrome bookmarks, check your spelling, find your contacts, translate text, and on and on.