Document shift+click behaviour on grouped controls

include/region-slip-drag.html

@@ -0,0 +1,18 @@
+<p>
+It's possible to move the contents of regions in time, without moving the
+regions' start or end points. This is sometimes known as "slip editing".
+</p>
+<p>
+To do this, hold the
+<kbd class="mod1"></kbd> and <kbd class="mod3"></kbd> keys
+while dragging the region or regions. As you click, the cursor will
+change to a double-headed arrow, and when you start dragging, the time from the
+start of the underlying content to the start of the clicked region is displayed.
+</p>
+<p>
+<img src="/images/slip-drag.png" alt="region slip-drag"><br>
+As you drag, the region start and end points will remain
+fixed, but the audio or MIDI content of the region will move,
+as long as the underlying source extends beyond the region bounds.
+</p>
+

include/the-track-and-bus-group-list.html

@@ -1,6 +1,9 @@
 
 <p>
-  This shows the track/bus groups that exist in the session. These groups allow related tracks to share various properties (such as mute or record enable state). For full details, see the section called <a href="@@the-track-and-bus-group-list">Track and Bus Groups</a>.
+This shows the track/bus groups that exist in the session. These groups allow
+related tracks to share various properties (such as mute or record enable
+state). For full details, see the section called
+<a href="@@track-and-bus-groups">Track and Bus Groups</a>.
 </p>
 
 <p>

include/track-and-bus-groups.html

@@ -123,6 +123,22 @@
   way to make edits apply across all tracks in the group.
 </p>
 
+<h3>Overriding grouped status</h3>
+<p>
+It's possible to override the shared status of any properties of a group.
+Holding <kbd class="mod3"></kbd> while clicking on a grouped channel's
+Mute, Record Enable, In &amp; Out monitoring controls, or fader, will invert
+the sense of sharing of that control.
+
+<p>
+For example, if a channel is a member of an active group
+with "Record Enable" shared, <kbd class="mod3"></kbd>+click on that
+channel's Record Enable button will toggle only that channel's record enabled status.
+If a channel is a member of an inactive group, or of an active
+group that does not have "Record Enable" shared, <kbd class="mod3"></kbd>+click
+on that channel's Record Enable button will enable or disable the record enable
+status of all channels in the same group.
+
 <h3>Group Tab Context Menu</h3>
 <p>Context-clicking on the group tab offers a further menu of group-related actions. </p>
 <table class="dl">

master-doc.txt

@@ -1244,6 +1244,13 @@ uri: editing-and-arranging/change-region-lengths/pushpull-trimming
 part: subchapter
 ---
 
+---
+title: Move Region Contents
+include: region-slip-drag.html
+link: region-slip-drag
+part: subchapter
+---
+
 ---
 title: Stretching
 include: stretching-regions.html