Added Quick Mode section and reference from timeline jumping; including clock icon

docs/content.md

@@ -107,7 +107,7 @@ The minimum Speed value is **0.1 times** the normal Minecraft Tick Speed, and th
 To the right of the Speed Slider, there is the **Replay Timeline**.
 On the Replay Timeline, you see a yellow cursor indicating your current position in the Replay.  
 By clicking somewhere on this Timeline, you will travel in time towards the specified point in time.  
-Please note that it takes longer to do larger steps in time or to jump backwards in time.
+Please note that it takes longer to do larger steps in time or to jump backwards in time (see also [Quick Mode](#replaying-quickmode)).
 
 ## Camera Paths [paths]
 ### Introduction [intro]
@@ -429,6 +429,14 @@ If you have a Replay in a dark setting (for example at nighttime, or in a cave)
 
 This works as a replacement for the **Night Vision Potion Effect**, without the side effect of a weird sky color.
 
+## Quick Mode [quickmode] (Minecraft 1.9 and up)
+![](img/quickmode-icon.jpg)
+In **Quick Mode**, this clock symbol is displayed in the lower right corner of the screen.
+
+When you first enable **Quick Mode** in a replay, an internal reference of certain entity and block properties is stored for quick access, allowing for faster navigation in the **Replay Timeline**.
+As a side effect, certain features like particles and second skin layers will not be rendered in the preview.
+By default, **Quick Mode** is toggled with `Q`.
+
 ## Player Overview [overview]
 ![](img/player-overview.jpg)
 The **Player Overview** Screen