>Nothing :-)
>I found that if you select some ListItem tha has valuem then you can't turn it back to NULL.
That's true. Also comboboxes with RowSourceType = 5 put this NULL blank value at the bottom of the list, while other RowSourceTypes don't do this.
Anyway, in order to be able to switch back to blank value I add this empty value manually.
If it's not broken, fix it until it is.
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