timeline track that shows text in a dialog, can be configured to require confirmation 
https://adventure.softleitner.com/manual
 
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override Playable  | CreatePlayable (PlayableGraph graph, GameObject owner) | 
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| 
string  | Key | 
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| 
string  | Title | 
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string  | Content | 
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bool  | Confirm | 
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DialogButtons  | Buttons | 
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DialogResult  | Selection | 
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string  | TarketYesOk | 
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| 
string  | TargetNo | 
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string  | TargetCancel | 
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| 
string  | ClipName [get, set] | 
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double  | ClipStart [get, set] | 
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double  | ClipEnd [get, set] | 
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Dictionary< string, double >  | ClipStarts [get, set] | 
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ClipCaps  | clipCaps [get] | 
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