Configure the option "Maximum number of undo steps" (File | Options)

Here you can configure how many levels of undo are possible in Presentations.

Supported on: At least Windows Vista
Undo

Registry HiveHKEY_LOCAL_MACHINE or HKEY_CURRENT_USER
Registry PathSOFTWARE\Policies\SoftMaker\Presentations 2018
Value NameUndo
Value TypeREG_DWORD
Default Value99
Min Value1
Max Value999

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