struct ShareButton: View {
...
let byLine = currentlyReading.book.byLine
ShareLink(
item: image,
message: Text(byLine),
preview: SharePreview(byLine, image: image))
When sharing a book, the following is logged in console and the message field is not filled by byline as expected:
BookClub[14058:2642949] [NSExtension] Extension request contains input items but the extension point does not specify a set of allowed payload classes. The extension point's NSExtensionContext subclass must implement `+_allowedItemPayloadClasses`. This must return the set of allowed NSExtensionItem payload classes. In future, this request will fail with an error.