A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
Use the UPPER function around the existing formula so only the displayed text is uppercase while the sheet (tab) name stays lowercase:
=UPPER(MID(@CELL("filename",B1),FIND("]",@CELL("filename",B1))+1,256))
This converts the extracted sheet name to uppercase in the cell without changing the actual tab name.
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