why webview fallback not work

[erdie2613]

Important: This demo is still being maintained, but is now automatically generated via llama-pack. We strongly recommend developers who want to bootstrap their Trusted Web Activity project to use llama-pack. Since the content in this repository is now automatically generated, we'll also be closing the issue tracker. Issues should be filed directly in bugs.chromium.org, using this template.

If you have a Trusted Web Activity related question, the best place to ask it is on StackOverflow, on the trusted-web-activity tag, which is also monitored by the team.

Describe the bug A clear and concise description of what the bug is.

when i disable chorme browser to test fallback with webview,it not work!

To Reproduce Steps to reproduce the behavior:

1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Expected behavior A clear and concise description of what you expected to happen.

Screenshots If applicable, add screenshots to help explain your problem.

Smartphone (please complete the following information):

• Device: [e.g. iPhone6]
• OS: [e.g. iOS8.1]
• Browser [e.g. stock browser, safari]
• Version [e.g. 22]

Additional context Add any other context about the problem here.