Vanadium provides 3 different apps: browser, WebView and library. The browser and WebView both depend on the library. If you have another browser installed in the profile, disabling the browser won't break anything.
nodsocket Custom tabs are a feature that can be provided by any browser.
andrewteg Disabling the Vanadium WebView or library is broken. Disabling the browser is only broken if you don't have another browser installed in the profile providing the required interfaces for other apps.