User Configuration > Administrative Templates > Microsoft Project 2016 > Project Options > Interface > Show indicators and Option butons for
User
HKCU\software\policies\microsoft\office\16.0\ms project\options\interface
Specifies that the feedback triangle should appear in a corner of a Task Name field if you change the task's start date or finish date. If you enable this setting, a feedback triangle is displayed in the corner of the Task Name field if the user changes the task's start or finish date. If you disable or do not configure this setting, the user's default setting is used.