I have tried all that I have found on Google regarding removing the gray shadow from hyperlinks on LibreOffice Calc spreadsheets:
1. There is nothing in Tools >>Options
2. Styles >> Text > Hyperlink > modify does not work: the only shadow check box on Font Effects is already unchecked.
AFAIK, the grey “shadow” or background is part of the hyperlink formatting.
Do you mean you want to get rid of the hyperlink and find standard text again? If such is the case, just remove the hyperlink by selecting the cell then hitting Ctrl + M.
As I thought. Thank you for your answer.