This may not be what you are looking for but it may help. A good place to look for extensions is Qlik Branch and/or github.
There is an extension on Qlik Branch that will allow you to email or copy the current selections to a clipboard. You can then email these to others with the current selection intact.
Hope this helps.
Kevin, thanks for your help!
There is an extension to export from Qlik sense mashup page. However, that extension does not allow export data from Qlik sense mashup for anonymous users.
However, the published Qlik sense mashup is public access WITHOUT Qlik sense user_id and password, how to make it to export data from Qlik sense mashup for Qlik sense anonymous user?