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After sessionStorage.js is included in the JS environment, the contents of the playerX_sessionStorage.js file are loaded and then pumped in via sessionStorage.fromJSON(data) (where 'data' is the string representation of the contents of the playerX_sessionStorage.js file).
That's it.
Future development:
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localStorage
If the sessionStorage idea proposed above gets accepted, then an obvious next-step would be to implement localStorage.
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