Hello , Thanks for reaching us. The tool you are looking for is "Add note to replace text". In the latest version two changes are done. This is removed from the tool bas as it was redundant and same functionality can be achieved using strike through text and adding popup note for it. The text correction commands (Insert text , strike through text and add note to replace text) are now enabled by default in comment app and need not to be selected from tools bar. You have to just, Select the text and start typing for Replace Text Press delete for Strike-through Start typing without selecting text for Insert Text Hope it will help. Thanks Acrobat Team
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