Add docs on quick groups for 8.0

include/quick-groups.html

@@ -0,0 +1,46 @@
+<p>
+	Having a persistent group of tracks and/or busses has a number of pros,
+	such as being able to control faders of multiple tracks at once, at any
+	moment in time. However, Ardour also supports "quick" temporary groups.
+</p>
+
+<p>
+	Selecting multiple tracks or busses either in the Editor or in the Mixer
+	window allows treating those tracks and/or busses as a group as long as
+	the tracks/busses are selected. This means:
+</p>
+
+<ul>
+	<li>
+		Adjusting fader position in one track/bus will change faders' positions
+		of other selected tracks/busses by the same amount. The same applies
+		to input trim changes.
+	</li>
+	<li>
+		Toggling Solo, Mute, Rec-enable, Solo Safe, Solo Isolate, Monitoring
+		controls in one track/bus will toggle the same type of control in other
+		selected tracks/busses.
+	</li>
+</ul>
+
+<p>
+	If one of the selected tracks/busses belongs to a persistent group,
+	selecting it will automatically all the other members of that persistent
+	group and affect respective controls there as well. This can be worked around
+	by opening group's setting and changing what controls are shared in the group.
+</p>
+
+<p>
+	There are two cases where quick groups will not work as expected:
+</p>
+
+<ol>
+	<li>
+		When a change to a control in a selected track/bus comes from a hardware
+		control surface.
+	</li>
+	<li>
+		When you use the mouse scroll wheel to adjust faders
+		(this is a temporary limitation).
+	</li>
+</ol>

master-doc.txt

@@ -754,6 +754,14 @@ uri: working-with-tracks/track-and-bus-groups
 part: chapter
 ---
 
+---
+title: Quick groups
+include: quick-groups.html
+link: quick-groups
+uri: working-with-tracks/quick-groups
+part: chapter
+---
+
 ---
 title: Monitor Section
 include: monitor-section.html