Can't test now but ChatGPT said this:

Creating a drop-down list in LibreOffice Calc involves using the Data Validity feature. Here are the steps to create a drop-down list:

1. Open LibreOffice Calc: Open your spreadsheet in LibreOffice Calc.

2. Select the Cells: Click on the cell or select the range of cells where you want the drop-down list to appear.

3. Open Data Validity: Go to the menu and click on Data > Validity....

4. Set Criteria: In the Validity dialog box, go to the Criteria tab.

   • From the Allow drop-down menu, select List.
   • In the Entries field, type the values you want to appear in the drop-down list. Separate each value with a comma. For example, type Option 1, Option 2, Option 3.

5. Optional Settings:

   • Go to the Input Help tab to provide users with instructions or help text when they select the cell.
   • Use the Error Alert tab to define how Calc should behave if an invalid value is entered.

6. Click OK: Once you've configured the settings, click OK.

Now, the selected cells will have a drop-down arrow, and users can choose from the list of values you defined.

If your list of values is long, you might want to reference a range of cells instead of typing each value manually. Here's how:

1. List Values in a Range: List your values in a separate column or sheet.

2. Name the Range: Select the range of cells with your values. Go to Sheet > Named Ranges and Expressions > Define. Name your range (e.g., MyRange).

3. Data Validity: Follow steps 3-4 above, but instead of typing values in the Entries field, type =$MyRange.

4. Click OK: Once you've configured the settings, click OK.

This method makes it easier to update your list of values without modifying the Data Validity settings.