Google Sheets double click fill down not working

Question

If I select a cell and then double-click on the blue dot at the bottom-right of the cell, the fill-down function does not work, nothing happens.

Sometimes it does work, in other cases/columns.

The cells below are empty, but that shouldn't matter.

There is no filter applied to the sheet.

If I select two cells and try the same thing, it doesn't work.

Help appreciated.

(also posted in the Google Sheets support forum)

Answer 1

The solution I used was to select the first cell, scroll down to the last cell, hold down shift, select the last cell, and then used CMD+D (Mac) / CTRL + D (Windows) to fill down into the selection.

There is a keyboard shortcuts page here

(Based on the original answer here)