I did some performance test, just compare exceljs with https://github.com/SheetJS/js-xlsx/ and xlsx-populate js lib.
js lib and version:
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I tested it on web browser.

exceljs vs xlsx.js vs xlsx-populate
parse .xlsx file:
1MB file parse:
882.985107421875ms
2481.923583984375ms
1339.385009765625ms

15MB file parse:
13153.964111328125ms
exceljs crashed
22480.077880859375ms

exceljs is so slowly.
any plan with better performance?
thank you.