Apps: Save action stores files in a mystery location

[microbit-matt-hillsdon]

I can't find the file after Save completes and even if I could I'm not sure how the user is supposed to without browser UX for Downloads.

[microbit-matt-hillsdon]

The current plan is to replace this with a share action. TBD how successful this is.
But I'm not honestly 100% convinced about this.

[microbit-matt-hillsdon]

See also the JSON downloads.