JAL-1445 basic help docs for feature

diff --git a/help/html/features/featuresettings.html b/help/html/features/featuresettings.html
index c8e6bc4..ed18ae7 100755 (executable)
--- a/help/html/features/featuresettings.html
+++ b/help/html/features/featuresettings.html
@@ -37,7 +37,16 @@ they are currently being displayed (only the ticked features and groups
 are displayed). <strong><em>You can change the colour or
 shading style used for a feature in the associated alignment by clicking
 on its colour box.</em></strong></p>
-<p><strong><em>Feature settings pop-up menu</em></strong><br>
+  <p>
+    <strong><em>Selecting alignment columns by feature</em></strong><br>
+    <strong>Double-click</strong> a feature to add all the columns where
+    that feature is found to the current column selection. <strong>Shift+Double-click</strong>
+    will add all the columns where that feature is <strong>not</strong>
+    found. You can also find these options in the feature's pop-up menu
+    (see below). <br />
+    <em>Select columns by feature was added in Jalview 2.8.1</em>
+  </p>
+  <p><strong><em>Feature settings pop-up menu</em></strong><br>
 <strong>Right-click</strong> on a feature to open a pop-up menu that
 allows you to sort the alignment or current selection using that feature
 type (see below), or toggle the type of colouring used for the feature.