OptionaldefaultBoolean value indicating whether the action is the default action for a message item in Facebook Messenger.
OptionalextraThe fallback uri for channels that don’t support webviews. Used for actions of type webview.
OptionalmetadataOptionalopenBoolean value indicating if the webview should open automatically. Only one action per message can be set to true. Currently only supported on the Web Messenger.
OptionalsizeThe size to display a webview. Used for actions of type webview.
The button text.
The type of action.
The webview URI. This is the URI that will open in the webview when clicking the button.
When a webview actions is clicked/tapped, the provided URI will be loaded in a webview. Channels that do not support webviews will open the fallback URI instead.