The developer can use the <std-toast> HTML element to pass in custom HTML content for the toast, but there is currently no way to do this for the showToast() function.

This could be solved by passing in an HTML template string as the message parameter of showToast(message, options), for example:

const toast = showToast(`<b>Hello</b> World!`);

Is there interest in supporting this behavior, or is the current option sufficient?