Cannot Drag to Select Multiple Cells

Hi community,

I have a user who cannot select multiple cells by dragging the handle with the cursor.
What's strange is this only occurs when interacting with a sheet on an external monitor. The functionality remains fine on the inbuilt display.

Troubleshooting I have already tried:

• Restarting
• Using a completely new blank sheet / workbook
• Physically troubleshooting the display connection
• Setting the external monitor to be the "Make this my main display" in display settings
• Disabling the inbuilt display
• Rearranging the displays to be perfectly in line
• Ensuring all displays are the same resolution
• Changing display scaling to match (used 100% for all)
• Setting magnification in Excel to 100%
• Restarting after these changes
• Making sure scroll lock is off

The user can still select multiple cells using keyboard shortcuts (holding shift and using arrow keys).

They reported that this issue was present after booting the laptop this morning and no other errors or changes were noticed.

I've had no other users report this issue and I can't recreate the issue either.

Any help is super appreciated. Thanks so much everyone.