This directory is concerned with the management of Lacros's startup parameters.

Startup parameters are passed by Ash's BrowserManager to Lacros via memfds. The fd numbers are passed to Lacros via command line arguments defined in startup_switches.

Startup parameters belong to two classes: BrowserInitParams and BrowserPostLoginParams. That's because Lacros supports being pre-launched at login screen, when user-specific parameters are not known yet. Accessing startup parameters via BrowserPostLoginParams before login blocks, waiting for login.

BrowserInitParams and BrowserPostLoginParams are not to be used directly. Instead, Lacros code should use BrowserParamsProxy which dispatches to either BrowserInitParams and BrowserPostLoginParams based on whether Lacros was prelaunched at login screen or not.