There is a bit of misunderstanding about permissions that web browser prompts for before installation of Ant Video downloader.

In order to use a portion of browser's application programming interface (API) an extension specifies in its manifest a keyword under permissions section. Once keyword is specified, web browser allows the extension to use API. It does not matter whether extension actually uses whole API or only part of it, the keyword must be present in extension's manifest file. In turn, web browser notifies user about the fact that one or several permissions are required by extension without going deep into technical details. Web browser does not check how much API does extension actually use.

Ant Video downloader utilizes several permissions in order to function properly. Without those permissions AVD won't work at all, or will work in cumbersome manner.

WebExtensions (and AVD is built using WebExtensions technology) are running sand-boxed and don't have access to whole system.

More information on AVD and WebExtensions:

• Manifest file format: https://developer.chrome.com/apps/manifest
• What are extensions?: https://developer.mozilla.org/en-US/Add-ons/WebExtensions/What_are_WebExtensions