You can enable and disable the Fill Handle feature in Excel settings. If you disable the Fill Handle feature, the white cursor will not change. This is what happens ...

Q. In the past, I could enter 1/31/2019 in cell B1 and 2/28/2019 in cell C1, highlight both cells, and then drag the Fill Handle to the right to generate the headings 3/31/2019, 4/30/2019, 5/31/2019, ...

1. Drag the Fill Handle of a single cell to copy that cell. The Fill Handle is at the bottom right of any selected cell or group of cells. 2. Drag the Fill Handle of a cell containing January, Jan, ...