amp-story-social-share: share to Instagram story

[swissspidy]

Description

By default, when using the system share dialog on a story, it allows you to simply share the link via Instagram.

However, apparently it's possible to provide a files list to navigator.share to enable posting to Instagram Stories or publishing as a post.

I think that would make sense for stories, maybe by sharing the poster image or dynamically creating a cover.

See https://stackoverflow.com/questions/17673156/instagram-share-photo-from-webpage/74802803#74802803

Alternatives Considered

N/A

Additional Context

No response

[erwinmombay]

@ychsieh please triage when you are back. thanks

[ychsieh]

Will bring this back to the team. At the same time also feel free to make the changes directly and we will be happy to review!