Thanks. I haven't seen that one before, it looks good.

I actually just use idb-keyval for my projects now.

https://github.com/jakearchibald/idb-keyval

It basically skips all the versioning and multiple databases capability and makes a storage as simple as localstorage but with all the perks of IDB like DB size limits and ability to store objects.

Check it out if you don't need all the other bits IDB offers.