In my searches, I've learned that a formula cannot return an empty cell AND I've also learned that the fact of a formula existing in the cell will cause this problem, as well.
Yes.. if you apply a formula to a cell, that cell is now filled up and can return blank using formula only e.g. "" but again it is a formula that is showing this blank

So basically you want, if any entry is entered in "Tasks" sheet, same info will show in sheet timeline .. but you don't want any formula in in timeline sheet or what ?

Regards,
DILIPandey

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