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 On mobile browsers (touch devices), a speech-bubble button next to the fullscreen button overlays the current slide with its speaker notes -- useful for practicing a talk on a phone or tablet, where the separate speaker view window of the `'s'` shortcut is awkward. The overlay shows the slide title, its planned time (if annotated with a timing comment), and the notes, and follows along as you change slides. It appears only if the deck contains notes at all.
 
+-   `'r'` toggle the transcript view: a single scrollable page containing every slide's content and speaker notes, so text-to-speech ("read aloud") browser extensions can read the whole presentation -- they cannot walk a reveal.js deck themselves, since hidden slides are not part of the visible page text
+
 -   `'m'` enable menu mode when the 'menu' plugin is activated
 
 Pressing `Esc` exits all of these modes.