Configure the option "Cell marker: Thickness" (File | Options)

Here you can configure the thickness of the border around the active cell.

Supported on: At least Windows Vista
CellMarkerThickness

Registry HiveHKEY_LOCAL_MACHINE or HKEY_CURRENT_USER
Registry PathSOFTWARE\Policies\SoftMaker\PlanMaker 2018
Value NameCellMarkerThickness
Value TypeREG_DWORD
Default Value2
Min Value1
Max Value5

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