How does the browser handle access control to the local storage, especially offline when they aren't loaded from the same site?
[Yes, I really don't know. Yes, I'm asking. Not everyone is a web dev.]
> As TabSub uses local store this only works on the same domain, as the browser separates the local storage by domains as security measure.
(More precisely, the separation is based on origin, which is roughly the combination of protocol, hostname, and port.)
The conclusion is this only works between tabs that have the same website open.
You can try on the demopage when you
1. play the songs each (for them to buffer a little audio snippet)
2. open the page in a second tab
3. Disconnect from the internt
Still works :D
(like me for your question, as I never tried TabSub with internet disconnected. Was delighted to see it works nevertheless)