misbehaving data validity

I use Validity with cell range. I do not want to see white lines (fields) in Validity cell if there is nothing visible in the cell of the covered range. I have a range of >100 cells of which about 10% contain visible data. The data is concatenated.
If I refer to a cell with “nothing” as a date source the date formula returns the zero value of win10 date, implicit cell containing 0, which it does not! If Data Validity refers to an “empty” looking cell which contains a formula the Validity cell shows an empty menu line as a nuisance. The setting of Allow Empty Cells is ignored, does not matter. The invisible formula is treated as an entry. Compare the logic!
I use the validity cell to see where there is a column with an entry. The entry consist of a date Dec-31 and a action note, concatenated. The range of applicable columns is >100.
LO has been distributed for many years already. I can not understand why SoftWarriors operating as Trouble-Hunters have not corrected this matter.

I spent considerable time to prepare an example sheet. There seems to be no upload here. I’ll try OpenOffice with the sheet.

There seems to be no upload here.

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Cross posted at [Solved] Misbehaving data validity (View topic) • Apache OpenOffice Community Forum

If you cross post, please note that you have done so, otherwise it leads to several discussions and a waste of time because several identical answers may be posted by different users.

here is the file, and thanks for the upload pointer
}Validity failure LO Forum 20201129.ods