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By default, the timestamp iink uses are encoded on a int 64. we consider these are in miliseconds. Values such as timestamp since Unix EPOCH can be provided.
If decimal values are provided, by default a cast to int 64 will be done.
Basically, the easier is to provide miliseconds as int 64.
in the given link https://developer.myscript.com/docs/interactive-ink/1.5/web/iinkjs/editing/#series-of-events
the list of 't' is list of some decimal values, what is the type/EPOCH of that timestamp?