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In our Spreadsheet component, users can define and use custom formulas on the client side, and these functions work as expected during runtime. However, when exporting the spreadsheet as an Excel file, any functions that are not recognized by Microsoft Excel are ignored. Instead, the calculated values from those custom functions are included in the exported file
And we need to provide option like `includeCustomFormula` in the server side and enabling the option will include the user defined formula's in the exported file if needed by the user. Below attached the screenshot for reference.
Default (without including custom formula):

After enabling this option (including the custom formula):
