Isolated Web applications (IWAs) are defined as applications which, rather than being hosted on a live web server and fetched over HTTPS, are packaged into bundles signed by their developers and distributed to users through various methods including platform-specific installation formats like APK, MSI, or DMG, raw singed bundles, through an operating system, browser or third-party “app store,” and installed via enterprise system configuration management infrastructure.
IWAs can be more secure
Google’s attempt at this feature probably draws from the fact that IWAs are comparatively secure as they limit the interaction and sharing of data between different applications and systems. The benefits of operating an isolated web application include compromise containment, controlled access and permission, reduced dependency risks, and protection from cross-site scripting attacks.
Post this update, IWAs with permission to use the “USB unrestricted” feature will be able to access a USB device normally “restricted” under the “vulnerable devices” blocklist. The feature will presumably allow customizing the types of USB devices accessible even when “USB unrestricted” is on.