[IndexedDB] How to recover data from IndexedDB if the origin domain don't exist anymore?

I have been looking on Internet and reading the spec but didn't be able to
get at answer.

Let's see the next situation: I've developed a webapp that use IndexedDB to
store personal data. It's pure client-side and server-less, being all the
content of the webapp just static files and served with static web servers
and CDNs, so all the user data is stored on IndexedDB on the user's
computer and not any other place (there's no a "database server" that could
be accesed in any form in any place at all).

I know that IndexedDB use a same-domain policy to isolate the access to the
data, but maybe one day the domain of my webapp could dissapear for any
reason (bankrupcy, forgot to pay the domain renoval, legal issues, system
fail... whatever) so I can't be able to access to the page to download the
webapp that would allow to me to access to MY data in MY computer.

At this moment, I've developed a way to make backups of the content of the
IndexedDB so it could be "imported" on the IndexedDB of other domain (and
also on other computer if neccessary) but I find it bad for usability, so
my question is, there's a way so an IndexedDB database could be shared by
several domain unrelated webapps? Maybe defining in some way a "fake"
origin for the IndexedDB object that all the webapps could have in common
(in some way like a "magic word"), or the specification doesn't allow this
possiblity at this moment? If so, how I could be able to do it?

Greetings and thank you very much, Jesús Leganés Combarro.

Jesús Leganés Combarro
piranna@gmail.com
http://github.com/piranna/ShareIt


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