Firefox on Android can now work with Trusted Web Activities, something previously only available through Google Chrome and other Chromium browsers.
Trusted Web Activities (TWAs) are essentially websites or web apps that run in a modified Chrome Custom Tab. TWAs exist as one of Google’s many options for app developers opening web content within apps.
Typically when users open web content from an app, one of a few things will happen. Either the link opens in the default browser, it can open the content in WebView, an embedded, sandboxed and limited option, or a Custom Tab. TWAs mostly operate as a version of Custom Tabs that don’t display any user interface (UI) and have some extra restrictions developers must adhere to.
Alternatively, some Play Store applications operate as web apps running inside TWAs, almost like a Progressive Web App (PWA) with extra steps. Android Police notes that Google Maps Go and PhotoStack are examples of TWA-based apps you can install from the Play Store.
These apps previously only worked with Chrome, which meant even if you had a different default browser, they would still use Chrome or a Chromium-based browser. Now Firefox Nightly supports TWAs and can run them instead of Chrome.
Unfortunately, the support isn’t perfect. It should come as no surprise given that Firefox Nightly often contains bugs. Android Police reports that some TWA apps work, but Firefox doesn’t hide the browser UI. The point of TWAs is to hide the browser UI for a more seamless experience.
Other TWAs, like Google Maps Go, have built-in checks that look for Chrome and prevent the TWA app from working on other browsers.
Of course, Firefox Nightly still represents Mozilla’s early efforts in supporting TWAs. That said, TWA support has been live in Nightly for a while now. Hopefully Mozilla can iron out the kinks before TWA support moves to Firefox Beta, which should happen soon.
Source: Android Police