The ABR client is downloaded as an installer file from the Internet via the ABR portal. Starting with Windows 8.6, the installer includes a browser extension, which monitors all subsequent downloads on that endpoint.
A few FAQs about this extension:
What does the browser extension do?
Basically, the browser extension listens for the “download finished” event in the browser. Once the event triggers, it uses Native Messaging to communicate with the ABR client and shows a toast notification with info about the downloaded file:
Once the user clicks the notification, the extension once again uses Native Messaging to communicate with the ABR client – telling it to trigger the flow just as if the user had opened the file via Explorer.
Which browsers are supported?
The extension is built for Chrome and Chromium-based browsers:
For Google Chrome, the extension is fetched from the Chrome Web Store.
For Microsoft Edge, the extension is fetched from the Edge add-ons site
How is the extension installed?
The extension is installed and configured via registry keys specific to the individual browser. This ensures that the user does not need to do anything to use the functionality of the extension.
See also browser notifications - settings and video and browser extension registry values.