Differences in support/behavior compared to Chrome

Quiet interstitials

The main interstitials in Chrome are Loud interstitials, which are blocking pages that show detailed informational text to users and are (usually) red in background color. WebView supports these interstitials when we believe WebView is the predominant part of the application UI (such as in browser apps).

When we suspect WebView is a smaller (or otherwise less prominent) part of the application UI, we show a gray Quiet interstitial, which is meant to feel like a less-scary error page.

There are Small, Medium, and Giant Quiet interstitials. Medium interstitials are when we have enough space to show textual information, Small interstitials are when there's not enough space, and Giant interstitials are whenever part of the WebView hangs out of the viewport.

Small interstitial	4 Medium interstitials	Giant interstitial (hanging off bottom right of viewport)

Network error

WebView returns a particular network error to the application when the user clicks “back to safety.” This is to stay consistent with expectations of legacy applications (to communicate the page failed to load).

Callback API

WebView supports the onSafeBrowsingHit() callback, allowing applications to implement custom interstitials. This also involves exposing threat type constants, to indicate what threat WebView observed.

Sometimes, no “back to safety” button

WebView will not show a “back to safety” button on the interstitial if there‘s no previous page in the history, or if we’re showing a Quiet interstitial.

With “back to safety” button (like Chrome)	No “back to safety” button (WebView only)