Good:

• Payment handler for "basic-card".
• Payment handler for "https://rsolomakhin.github.io".
• Payment handler for "https://rsolomakhin.github.io" that cannot make payments.
• Payment handler for "https://bobbucks.dev/pay".
• BobPay registration. Test it out with payment sheet. Test it out without payment sheet.
• Payment handler for testing selection of the best icon.
• Payment handler for testing payment method change event.
• Payment handler for testing shipping address change event.
• Payment handler for testing shipping option change event.
• Simple Payment handler for testing shipping/contact delegation.
• Simple Payment handler for testing contact only delegation.
• Simple Payment handler for testing shipping only delegation.
• Payment handler for testing microtransactions.
• Password handler.
• "src-card" method.
• SRC.

Bad:

(These payment handlers have bugs in their JavaScript.)

• Payment handler that does not specify the method name in the response.
• Payment handler that does not specify the details in the response.
• Payment handler with invalid instrument icon type.

(These payment handlers have bugs in their manifests.)

• Payment handler without a manifest link.
• Payment handler with manifest that cannot be downloaded.
• Payment handler without icon definition.
• Payment handler with icon that cannot be downloaded.
• Payment handler without a name definition.

(These payment handlers redirect to dangerous content.)

• Self-signed certificate.
• Phishing page.
• HTTP.

(This payment handler shows insecure content in the window.)

• Mixed content images.
• Mixed content JavaScript.