Configure the option "Scrollbars: Vertical" (File | Options)

Here you can configure if TextMaker shows a vertical scrollbar for the document.

Supported on: At least Windows Vista
Registry HiveHKEY_LOCAL_MACHINE or HKEY_CURRENT_USER
Registry PathSOFTWARE\Policies\SoftMaker\TextMaker 2018
Value NameVertScroll
Value TypeREG_DWORD
Enabled Value1
Disabled Value0

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