In Google Sheets, when I use "Data Validation" with a "List of Items", then a drop down list of the items is created. When I try to select values from the list, strange things happens. If I select the value and then navigate to the next cell by using the Tab key, or one of the arrow keys, all is fine. However, if I use the Enter key (a.k.a. Carriage Return), then, unlike any other entry of data in cells, I will end up losing the item I just selected, and the value will revert to a different value than the item I just selected. Apparently Sheets doesn’t respond properly to the Enter key. I checked the same in Excel, and it does the right thing.
Platform is a Chrome on Windows (x86).