Normalize storage event

Love the package! The normalization it tries to do for browser storage is awesome, except I noticed that it does not provide the same normalization for the storage change events.

For localStorage / sessionStorage, the spec includes a standard storage event that notifies of the change (https://developer.mozilla.org/en-US/docs/Web/Events/storage), and there is a similar fallback for cookies (https://developer.mozilla.org/en-US/Add-ons/WebExtensions/API/cookies/onChanged). It would be pretty sweet if we could normalize that to a standard event that you could listen to on the imported object, something like

import storage from 'local-storage-fallback';

storage.on('change', () => {...});

This would facilitate cross-tab communication more in line with the localStorage spec, even if cookies are used. What do you think?

[dfdeagle47]

A side note if anyone is looking to implement this: normally, the “storage” event is only fired in tabs that did not initiate the change.

However, on IE11, the “storage” event is fired on all tabs (even the one that triggered the change).

If the storage event is normalized, we’d have to decide whether we want to keep the IE11 behavior for all storage fallbacks, or fix this issue as well. Personally, I’d fix it to normalize the behavior across all browsers.

[planttheidea]

Yup, I think that would work. Logically if cookie storage was used the storage event would not exist, so you’re not trampling over native events.