Hey, createInstance tries to open an existing store (depending on the driver in use) with the provided name and only when that's not available it creates a new one, in the exact same way that config() can be used to change the store name of the default LocalForage instance. It's surprising that you mention that this doesn't work for you.
Can you provide more details on the hard refresh and the browser that this happens? Any chance the browser was in private mode?

@thgreasi Seems that safari will create mutiple instance rather than find exist instance

@thgreasi The documentation is horrible! Nowhere is it covered how the check for existing storage occurs except here, found by sifting through the issue list.. Understanding these things is key to deciding on a solution, not very inspiring or respectful of others time.

Please just add "createInstance tries to open an existing store (depending on the driver in use) with the provided name and only when that's not available it creates a new one" to the documentation It would probably take the same amount of time as answering a users question.

@gregbown Thanks for the hint.
Here is a PR that addresses that #982 .