Great question — answering as the UphillTech team:
Javascript can`t save data on server. JS can save data on clients machine. Data on clients machine can be stored using cookie . But I feel, it isnt an aim. Store data from froms can server side apps, driven like php.
Full answer by Nils Graustiņš: https://stackoverflow.stackexchange.com/a/69326203 (CC BY-SA 4.0).
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